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In the face of intense global competition and other business pressures on coal miners, ongoing quality initiatives and continuous process improvements are needed to enhance business performance. By viewing a minesite in terms of key processes, rather then departments, and employing innovative technologies and better applying organisational resources, there exists enormous potential to achieve reductions in process cost and time.

Jan 1, 1998

By Jin C, Shi X

The studies of pulp electrochemical flotation separation of pyrite and arsenopyrite were made from the thermodynamics, mineral natural oxidation rate, property of mineral surface oxidised material and pulp electrochemical flotation tests. The results showed that although pyrite and arsenopyrite possessed similar thermodynamic stability, significant differences of two minerals were observed in natural oxidation rate, property of surface oxidised material and its influence to dixanthogen formation on the oxidised mineral surface. Based on the non-thermodynamic differences, the pulp electrochemical flotation technology was successfully used to separate arsenopyrite from pyrite in pilot test.

Jan 1, 1993

Choosing an Effective Dust Suppressant

Sep 13, 2010

By Martin JD, McNicol JH

The electrolytic zinc plant at Port Pirie South Australia, was designed and constructed to treat zinc oxide fume recovered by treatment of lead blast furnace slag in two fuming furnaces, The plant was commissioned in late 1967. The equipment installed and the oper- ating procedures adopted,'are described in some detail.

Jan 1, 1975

In conjunction with a study on wear of drag bits the effect of clearance angle on penetration rate was studied.Increases in clearance angle from 24 1/2 up to 30° gave an increase in penetration rate. Thereafter the rate was apparently affected by partial clogging with cuttings.Analysis of results was by a linear regression model and the t-test was applied to assess the significance of parameters in the penetration equation.

Jan 1, 1969

In a stipulated hard rock situation, drilling and blasting costs per tonne in open cutting or underground operations are comparable. In open cuts the drilling and blasting costs per tonne of ore are multiplied by the waste ratio.Conventional underground loading and haulage practices are so batch-oriented that the cost per tonne of ore handled is a large integral multiplier of open out costs per tonne loaded and hauled.If underground costs are to be reduced to compare favourably with open out costs then loading and hauling practices underground must be converted to a non-batch continuous system. This can be achieved by utilising gravity to control ore to mobile crushers feeding conveyors running direct to surface.

Jan 1, 1985

By D R. van der Meulen, P Ande, D J. Lunt

Pressure hydrometallurgy is becoming an increasingly common unit operation in the treatment of gold and base metal ores and concentrates. The design of an adequate and appropriate pilot-scale testwork program is, therefore, essential in order to minimise the risks associated with developing a project in which autoclaves form a key part of the operation. This paper identifies the approaches that have been taken in the piloting of oxidative and pressure acid leach operations. Particular emphasis is placed on the determination of scale-up ratios between the pilot and commercial plants and the pilot-plant run durations. The issues, both metallurgical and project-specific, that can impact these key parameters are reviewed.

Jan 1, 2004

By Trevits MA

The United States Steel Corp. in cooperation with the United States Government is conducting a large-scale methane drainage field demonstration using stimulated vertical boreholes drilled in advance of mining. A grid pattern of 23 boreholes, isolating approximately 1.5 km2 of coalbed area, has been drilled to the lower bench of the Mary Lee coalbed, Jefferson County, Alabama. Upon completion of drilling operations, various hydraulic stimulation treatments utilizing nitrogen-generated foam, water, and gelled fluid were performed to enhance the rate of methane gas removal. Production from the grid pattern began in September 1977 and continued as the last borehole was placed on production during October 1980. To date, in excess of 33,800,000 m3 of methane gas has been drained as a result of this effort. Underground mining operations were approximately 3.2 km from the grid pattern when production began and have currently progressed to within 1.6 km. Underground interception of the grid is expected in 1986.

Jan 1, 1982

As this Seminar is on "Progress - Mining and the Environment", I am taking the liberty of extending my address beyond the scope implied by the subject, "Rehabilitation of Mined Land", with a preliminary discussion on broader economic issues relevant to "Progress and Mining in Western Australia" before discussing its effect on the Environments Western Australia is nearly one million square miles in area and has a population density of approzimately one person per square mile. Because of its vastness it has wider climatic variations than any other Australian State. The north is tropical and the south is in the temperate zone. The major portion of the State is an arid plateau with less than 10 inches of mean annual rainfall. The climate, rainfall and soil conditions of the South-West region are more favourable to agriculture than any other part of the State and consequently was settled first. The immediate need of the colonists being food and shelter, the early economy was based on farming and forest products.

Jan 1, 1971

Tonnes per Hour - Kilowatts per Tonne Tonnes of Mesh Size Produced Kilowatts per Tonne of Mesh Size Produced - Terms often heard in discussions of grinding mill and grinding circuit performance. All of them only tell a partial story as none of them relate to a fixed reference or overall standard measurement. Tonnes per Hour gives the production rate relating it to a specified or desired rate set as a goal or objective. As such it does not take into account changes in feed size, product size or grindability. Kilowatts per Tonne which accurately stated is kilowatt hours per tonne brings power consumed into the picture which is related to grindability but still does not take into account changes in feed size and product size without which power changes do not necessarily reflect the complete effect of changes in Grindability.

Jan 1, 1978

The results of iron ore exploration in Western Australia between '1961 and 1964 are outlined, with particular.reference to the Hamersley Iron Province. Exploration during: these three years has increased the known resources of the-,Statle from 275 million tons to almost 9,000 million tons of high- grade hematite ore. In addition, reserves of lower-grade .pisolitic limonite ore are-estimated to amount to 6,000 million tons. The origin and characteristics of the different types of ore is discussed,

Jan 1, 1964

By Guvenir HA

This paper summarises a cost optimisation procedure by minimising the total drill metres and the overbreak that occurs in tunnel excavation in medium strength rock (uniaxial compressive strength

Jan 1, 1995

By D Liang, L Zhang, X He

The sulfurisation-flotation process was unsuccessful when initially applied to the oxidised Pb-Zn ore in Lanping County of Yunnan Province China. A comprehensive mineralogical study indicates that the problem is caused by the soluble salt gypsum in the Lanping oxidised ore, which produces a large amount of Ca2+ cations. The Ca2+ cations react with S2- anions (from sodium sulfide) in preference to Zn2+ and Pb2+ forming calcium sulfide, and make it difficult to form zinc and lead sulfides on the surfaces of the respective oxidised Zn and Pb minerals. In addition, the calcium sulfide formation consumes a large quantity of the available sodium sulfide, further inhibiting the sulfurisation process. The efficiency of the sulfurisation of oxidised Zn and Pb minerals has been improved greatly by the pretreatment removal of gypsum, with the added benefit of the required dosage of sodium sulfide being substantially reduced.

Jan 1, 2008

Carbothermal Reduction and Nitridation of Ilmenite Concentrates and Chlorination of the Reduced Samples

Sep 13, 2010

By C Deacon

It is common practice to include microspheres or similar density reducing agents in inherently insensitive water-based commercial explosives to achieve detonative sensitivity in the absence of chemical sensitisation. It has recently become possible to similarly include microspheres in LDAN (low density ammonium nitrate). Further to previous studies and publications to determine the benefits resulting from the use of microsphere enhanced LDAN technology in blasting, additional advantages are described in this document. These include range tests at independent testing facilities (Universal Tech Corporation û USA) which reflect results observed in the field, and support theoretical assumptions made when the products were introduced. Additionally, on-site studies in opencast pits using Heavy-ANFO blends incorporating modified LDAN, show that monetary savings can be realised through significant advantages gained in plant throughput and explosives use.

Jan 1, 1999

By Groves J

The sizing and classification circuits at the Mt. Newman Beneficiation Plant have performed satisfactorily. Investigations have been aimed at solving minor problems and achieving small' improvements. Emphasis has been placed on cost reduction rather than metallurgical performance. It has been found that some circuits will give better performance with the sieve bends removed. 1.0 BACKGROUND Mt. Newman. Mining operates a major iron ore mine in the Pilbara region of Western Australia. Rainfall is sparse (average 250 mm/year). Current mining is all above the water table. What rain there is tends to run off quickly instead of soaking in. The total operation produces about 30 Mt/ year of saleable product. Most of this product comes from high grade crushing plants where ore from the quarries is simply crushed and conveyed to product stockpiles. About 3 Mt/ year comes from the Beneficiation Plant.

Jan 1, 1984

By Williams DJ

Preliminary calculations suggest that spoil piles in the Bowen Basin will undergo approximately 4 m settlement as the ground water table recovers after mining is abandoned. Approximately 1 m of differential settlement is possible. Superimposed on this will be a long term creep settlement of 1-3 m/log cycle of time. Depending on the nature of the spoil material, partially submerged spoil piles could be sufficiently stable although to ensure stability during long term creep it may be necessary to flatten the final spoil pile face to approximately 25¦.

Jan 1, 1987

By Van Rooyen F

An introductory review of the current grade control blasting techniques (selective mining strategies) used in the Eastern Goldfields has recently been undertaken. The survey was initiated and conducted by the Western Australian School of Mines. Four distinct selective mining strategies have been identified and a number of trends have been highlighted. Many operations, however, have developed techniques which use a hybrid method to suit the site conditions. The aim of all the mining strategies is to produce an optimum product. The optimum product is one which contains no diluent and experiences no mixing of the various identified ore and waste blocks and is fully reco- vered at the minimum overall operating cost. Due to this unified aim all of the grade control blasting techniques have many common design Features.

Jan 1, 1988

Diesel-engine exhaust emissions represent a concern to the mining industry due to the poten- tially harmful health effects of the pollutants, as well as high costs associated with providing proper ventilation to assure a healthful working environment. The control of exhaust emissions is complex since the operating mode and condi- tion of the engine, the mine environment, and the operator's skills all influence the concen- tration and composition of the emissions. It is not practical to measure each exhaust pollutant in underground mines; therefore, a monitoring methodology is required to measure the pollut- ants and assess the air quality.

Jan 1, 1988

By Ormsby W, Peters M, Van Gils H, Kehprens P, De Boorder H

The northern margin of the Arunta Block is characterized by a metasedimentary and volcanic sequence of lower metamorphic grade than that of the central Arunta Block. Whereas the Harts Ranges have granulite to amphibolite metamor- phic grades, the northern margin only reached greenschist to lower amphibolite facies. Most of the high grade area of the central Arunta Block appears to be unprospective, but the lower grade marginal fringe contains most mineral pros- pects to name a few: Barrow Creek, Molyhill and the Jervois Mine. Numerous smaller prospects occur in this marginal zone. Four major lithostratigraphic units can be recognized in the Jervois Mine area: 1. Gneissic Suite consisting of granitic and rhyolitic gneisses which are characterized by a distinct intersection lineation. 2. Metasedimentary Suite of cordierite- biotite schists and chlorite-biotite schists. 3. Mine Sequence, consisting of spotted schists with andalusite and cordierite, quartz- sericite-feldspar schists with distinct rhyo- litic remnants and quartz-sericite-feldspar schists which contain the lode horizons:

Jan 1, 1984