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Conservation and environmental issues are raising their profile with respect to both demand restraint and electricity supply options. In New Zealand, conservation pressures and energy efficiency need to be seen in relation to the supply system currently in place which has capacity for economic supply of electricity in quantities substantially in excess of the current market. Consequently, energy efficiency and conservation need to be interpreted in relation to the supply system as well as in relation to end use. The relationship between the environment and conservation is strongest when new generation is required. New Zealand's electricity supply system consists of a large proportion of hydro production and this has significant environmental benefits when considered in relation to concerns of global wanning and the greenhouse effect. However, environmental trade-offs in supply options need to take account of both the efficiency of electricity end use, the trade-off between hydro and thermal generation and the inter-regional effects of shifting development options from one region to another. The Electricity Corporation has a high level of consciousness with respect to environmental and conservation issues and this paper demonstrates its own moves to maximise energy efficiency and illustrate the environmental trade-offs for supply.

Jan 1, 1990

By L Xiong, W J Shi, J H. Wei

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Baizhangzi gold deposit is located in the northern North China Craton. The structural and lithological controls on the location and geometry of orebodies were studied through geologic survey, ore spatial configuration analysis and structural analysis. The orebodies of the deposit comprise auriferous quartz-sulfide veins and disseminated gold-bearing sulfides. The auriferous quartz-sulfide veins are dominantly hosted by the NNE- (and NE- and NW-) trending faults, which are subsidiary structures of the regional NNE-trending F2 fault. The subsidiary NNE-trending faults, having sinistral reverse kinematics, are associated with the sinistral reverse kinematics event of the F2 fault, which happened under a regional S–N-oriented compression stress field. The subsidiary NE- and NW-trending faults appear to be compressive and extensional respectively. These NE- (and NW-) trending faults are restricted to the granite intrusion and are associated with a sinistral strike-slip event of the F2 fault, which reactivated under a NW–SE-oriented compression stress field. It makes significant influence on geological evolution and distribution of different ore types that the strike of the F2 fault presents significant transition from NNE- to NE-trending in vertical. The ore-bearing disseminated host rocks, with widespread silicification and pyritisation, distribute in the lower inner contact zone of the granite intrusion, especially in the lower wavelike boundary of granite intrusion.CITATION:Xiong, L, Wei, J H and Shi, W J, 2015. Structural and lithological controls on the location of orebodies in the Baizhangzi lode gold deposit in western Liaoning Province, China, in Proceedings PACRIM 2015 Congress, pp 193–200 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

Alluvial gold mining in New Zealand and in particular on the West Coast underwent a renaissance during the early 1980's. This was based on two main factors: a) the sharp rise in the gold price b) the advent of the hydraulic excavator with which to mine the auriferous gravels. The scale of operations varies considerably. A small operation typically consisting of one or two people using an excavator to feed either a land based or pontoon mounted (floating) gold recovery unit, which will typically feature a rotary screen with or without a tailings stacker with the screened fines < 10 - 15 mm) fed over riflle tables. The largest screening plants of this type are operated by DML Resources in their Arahura and Mikonui mining operations where the plants have the capacity to screen up to 250 m3 of gravel per hour. These plants usually employ jigs and centrifugal concentrators for gold recovery. Unique amongst current operations is the Grey River Dredge, a bucket ladder dredge capable of processing 700 m3 per hour similar to those that operated earlier this century. Gold concentration is by a series of jigs. The number of plants operating in recent times peaked at around 130 in 1987 (coinciding with a nominal average gold price of $751) and since that time has steadily declined to 80 units in 1993 and about 45 - 50 units today. This cycle of rapid expansion and then steady decline has been repeated on the West Coast since the original gold discoveries in the mid nineteenth century.

Jan 1, 1996

By T J. Scanlon

Heavy minerals recovered from recently discovered deposits in the Murray Basin are proving to be somewhat more difficult to process into saleable ilmenite products than ilmenites from existing operations. This is due to the nature of the gangue minerals present, the impurities in the valuable minerals and the size distribution of the mineral assemblages. Ilmenite product quality, in particular, can be adversely affected by any of these factors. Over the past two years the authors have been involved in assessing the potential to manufacture ilmenite products from a variety of mineral sand deposits in the Murray Basin. The steps undertaken to define the potential products and develop suitable flowsheets have evolved in parallel to the exploration efforts, in cooperation with companies undertaking exploration in the Murray Basin. A combination of an understanding of detailed mineralogy, application of magnetic fractionation and modification of magnetic susceptibility of the ilmenites has in all cases, been successful in improving ilmenite product quality. The targeting of particular ilmenites to specific downstream processes for TiO2 pigment manufacture is the most challenging aspect of this development.

Jan 1, 2001

By D Craw

A glasshouse experiment was set up to investigate arsenic uptake in rye corn grown in different arsenic rich substrates. Sods of material were taken from various locations and planted with rye corn seeds. The plants grew for 13 weeks after which time the above ground biomass was harvested. Analysis of the rye corn plants showed a narrow range of arsenic concentrations, which did not reflect the arsenic contents of the soil. Comparison of the results from this study with previous work showed the glasshouse rye corn to have lower arsenic concentrations in above ground biomass than rye corn grown in field conditions. The environmental conditions present on the tailings and water-rock interactions were considered the main factors involved with the difference in arsenic uptake between field studies and the glasshouse study. This suggests that bioavailability processes are influenced by a variety of factors and cannot necessarily be predicted by the use of soil factors or glasshouse trials alone as is often done when planning phytoremediation work and mine shut down.

Jan 1, 2007

By Veal FL

Technological changes in Portland cement manufacturing during past years have reflected changes in the economics and availability of various types of fuel such as coal, fuel oil and natural gas. The industry consumes a sig- nificant quantity of both thermal and electric- al energy. The nature of the process and its chemical constraints does however permit the use of comparatively low grade fuels such as high ash coal and high sulphur oil. In striving for increased daily kiln outputs and conservation of energy, there is a worldwide trend towards the use of dry process plants. Wet process kilns of about 2 500 tonnes per day assume massive component sizes which present difficulties in manufacture, and transport to plant sites. Large capacity dry process units in excess of 8 000 tonnes per day are now in operation using precalcination techniques in which part of the fuel is introduced in the static preheater section ahead of the kiln while the balance is added to the kiln in a conventional manner. This technique has virtually doubled the potential output of any given single kiln.

Jan 1, 1976

In-pit crushing systems have been known in the mining industry for many decades. The question whether in-pit crushing is a viable option has often been asked. More than 200 mobile and semi mobile crushing systems have been installed worldwide at various locations and applications. Economic pressures have forced mine operators to reconsider the use of a conventional truck-shovel operation and have contributed enormously to the development of in-pit crushing and conveying systems. The in-pit crushing concepts have varying mobility capabilities. These range from fixed, stationary crushing plants to semi-mobile and fully mobile crushing plants. All these systems are operated in connection with a conveying system. In general in-pit crushing systems have technical and economical cost advantages over truck-shovel operation, particularly as mine capacities increase and mines become deeper. The integration of an in-pit crushing system represents a significant up-front capital investment and the mine is only able to depreciate the capital investment over a sufficient mine life including plant capacity to realise the benefit of the much lower operating cost.

Jan 1, 2003

By Andrews S. J

Century is a shale hosted zinc, lead, silver deposit developed within gently folded, Proterozoic Lawn Hill Formation shales and siltstones, approximately 250 kilometres north-northwest of Mount Isa, comprising 118 million tonnes of stratiform mineralisation, averaging 10.2 per cent ,,inc, 1.5 per cent lead and 36 grams per tonne silver. The deposit is largely overlain by Cambrian limestone and younger Proterozoic sedimentary rocks, outcropping at only two places. Small discordant lode lead-silver deposits formed the basis of relatively small scale mining activity in the area for almost 100 years, exploration tenement covering the deposit being granted to CRAE exactly 100 years after the first mining leases were pegged in the area in 1887.Stratiform mineralisation occurs within three distinct blocks, bounded by normal faults and the unconformity between Lawn Hill Formation and overlying Cambrian limestones. The Termite Range Fault, a major northwest trending, regional scale fault system occurs adjacent to the northeast deposit boundary, while the Magazine Hill Fault, possibly a component of the east trending Little Range Fault system, forms the southern boundary of the deposit.

Jan 1, 1993

By Gabriella Mendez

Worthy of note in Miss Bailey's paper are her comments on the attitudes of mining companies and their managers where women were employed, she says, "..another possible pitfall is reverse discrimination where in an effort to avoid being branded as having shown a person favouritism, supervisors end up treating the person in a manner much less than they deserve. This is manifested in denying an employee such things as challenging work, educational opportunities, promotions, or in the case of staff, fair merit increases." and further she says, "It has been observed that the treatment of women in non-traditional roles such as mining is different than for men in the same environment. There are people who treat women worse and some who treat them better simply because they are of the other sex." These statements may sound unjustified to today's audience, and whilst we need to credit pioneering women with having tolerated, understood and worked towards improving the mining culture, the move towards total inclusion of women in the workplace is still growing.

Jan 1, 1995

By Gardner CE

Uranium occurrences and the probable Australian reserves are discussed and the recovery and processing methods used in treatment plants at Radium Hill and Port Pirie, S.A., Rum Jungle and Moline, N.T., and Mary Kathleen, Qid. are reviewed. The broad aspects of the application of nuclear power in Australia are then considered, and those factors of greatest significance are highlighted. It is these factors that are most likely to dictate the future role of nuclear generation in Australia. In commenting on private industry applications, the paper emphasises that each case must be considered on its own merits, and a warning is given that general statements can be misleading. In the long-term situation nuclear power is considered to be capable of playing a leading role and the discussion covers desalination and high load industries although short term applications appear difficult to justify. In non-power applications for nuclear energy reference is made to isotopes and the uses of nuclear devices in mining and civil engineering with a pertinent comment on safety.

Jan 1, 1970

To explain in any depth the industrial relations of Broken Hill I believe that it is necessary to trace some of the many happenings that created the present industrial climate. While appreciating that our relations with the local industry are relatively good, it must be pointed out that to preserve and improve this present situation a duty is owed to everyone connected with the industry (workers, share- holders, etc.) by management and unions to see that just and reasonable agreements are found for any disputes. If the companies ever take the local position for granted it would soon die, killed by someone who may get some short term benefit, but who would lose something of incalculable worth in the long run. Similar- ly if the unions were to adopt some of the "wild cat" methods adopted in other parts of

Jan 1, 1975

Before the arrival of the first Europeans, Aborigines living in the northern Flinders Ranges mined ochre - an earthy form of haematite used for pigment.The discovery of copper ore at Kapunda and Burra in the 1840s stimulated the early settlers to prospect further north along the ranges. Many of the new discoveries were not properly evaluated and companies were floated on the most tenuous evidence.

Jan 1, 1993

A BRIEF account of the water-power potentialities of Tasmania is given, together with possible applications of the power commercially. A short history of the Waddamana development is then given, and the main works are described.WATER POWER POTENTIALITIESTasmania is an island of approximately 24,500 sq. miles area (exclusive of small islands). An area of 12,000 sq. miles is at an elevation of over 1000 ft. above sea-level, and of 2300 sq. miles at over 3000 ft. above sea-level. Average annual rainfall varies from' over 140 in. on West Coast to 20 in. on East Coast, and for the whole island averages 48.5 in. The total water-power available, based on conservative figures for run off and efficiency, is 6,000,000 b.h.p. Only a small percentage of this total will, under present conditions, and under likely conditions in the immediate future, be capable of being developed commercially.An extensive hydro-metric and water-power survey is at present being carried out in order to collect information concerning the most promising water-power schemes. Already 400,000 b.h.p. has been located in different proposals, and there is still a large area of very likely country along the West Coast which has not been investigated yet. Tasmania thus has very vast power potentialities, which, combined with good ports and communications and wonderful mineral and timber resources, should augur well for the establishment of the great key industries, particularly chemical and metallurgical.

Jan 1, 1923

By Seneviratne SP

The excessive displacement of the seam floor in headings (i.e. roadways) called 'floor-heave' is often experienced in the underground mines of the Southern Coalfield of New South Wales. Apart from interfering with the mining operations, the phenomenon could be detrimental to the stability of the pillars left for support leading to an unpredictable increase in the subsidence of the overlying strata. The latter could pose a serious problem, particularly in the design of partial extraction layouts of mining for areas where subsidence is to be controlled. The susceptibility of the floor of different rock materials and thicknesses in a given `panel and pillar' partial extraction geometry was examined by two- dimensional Finite Element Modelling of the displacements, stresses and failure zones around the excavations. The modelling, assuming elastic behaviour of the materials, indicated that the maximum vertical displacements of the floor increased substantially as the Young's Modulus of the material decreased to less than 7GPa and the thickness of the layer increased. The results also discount the possibility of a properly designed panel and pillar geometry in the Southern Coalfield of New South Wales being unable to adequately control surface subsidence through the pillar, or its core independently of the yielded ribs, penetrating the floor.

Jan 1, 1992

By S E. Munro, P D. Munro

The commonly traded base metals concentrates of copper, lead, tin and zinc are sold by miners to custom smelters using contracts whose terms were generally established at the beginning of the 20th century or even earlier. Technical clauses in these concentrates for items such as payable metals and penalty elements do not reflect current realities of extractive metallurgical technologies and hygiene/environmental issues.It is an axiom that the miners and smelters have a symbiotic relationship. While the existing antique and arcane commercial arrangements serve the purpose of transferring money from the buyer to the seller, they are not likely to result in the industry achieving better overall technical and economic outcomes. By examining the cases for copper concentrates and zinc concentrates in particular, it will be shown that the practical application of these antiquated technical clauses does not drive the miners to produce the better quality concentrates that should be desired by the smelters. This is despite development of mineral beneficiation and hydrometallurgical technologies that would allow the miners to make better products.The adage that any extractive metallurgical problem in the smelter is cheaper to solve in the concentrator still generally holds.While nickel concentrates are only touched on lightly in this discussion because sales terms are more opaque than those for the other base metals, it is expected that the same conclusions will apply.CITATION:Munro, P D and Munro, S E, 2015. Base metals concentrate sales contracts – change Pavlov and the dog, in Proceedings MetPlant 2015, pp 46–60 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

By C Sylvestre

For the last 50 years, traditional safety management has improved safety performance by: • Fixing the environment (eliminating the hazard). • Improving the system (more/less rules, procedures etc). • Making safety more conscious (more/better interactions about the importance of safety). Although these approaches certainly have merit, and may be part of an overall solution, they are not enough to prevent many modern-day incidents. Today, these three approaches are used more than before, and are used better than ever before. Yet, workplace fatalities in Australia have stagnated from 2013 to 2019, as have the number of incidents, even serious ones. In the USA, workplace fatalities have increased by 15 per cent in the same period.

May 5, 2022

By Swanson AR, Nicol SK

A study has been made into the influence of feed size distribution on the flotation response of coal. The results show that a full description of the flotation response of a coal must not only consider the inherent floatability of the coal, but also, the size distribution of the feed to flotation. The performances of a number of flotation circuits were compared using a coal which was "poorly floating" because of its size distribution. Split feed flotation, two stage reagent addition, and reflotation of classified tailings all gave better yields than that obtained by conventional single stage flotation. The optimum flotation circuit for the washing of the coal in question, was reflotation of classified tailings.

Jan 1, 1978

By Just GD, Gillies ADS

The competitive coal market has required coal producers to put more effort into coal quality control. Successful quality control requires a good estimation of the in situ coal quality as well as a good estimation of the probable fluctuation of the in situ coal quality during production. Geostatistics offers a very promising way to meet this requirement. A geostatistical approach toward the coal quality control problem is presented. Two models, the prediction model and the conditional simulation model, have been developed for coal quality data from two large export coal mines in central Queensland, Australia. The mine planning and scheduling aspects based on this and other potential applications of the models are addressed.

Jan 1, 1990

Chemicals derived from petroleum raw materials satisfy so much of our industrial needs today that it is good to pause and realise two things -ò the petroleum chemical industry is so new, and the use of chemicals is a very old one.Petroleum is such an'abundant and convenient source of raw material that in little more than 30 years it has become the major source of supplyfor chemical rdanuf ctiree This paperw~l'l 'disc'uss t1.e main 'r`easons' for this rapid development by considering the : sub jest -under tkzree headings ea. Source of Raw Materials.b. The Impact of Petroleum Chemicals on Plant Design and Processes. ce Scme of the Major Chemicals Used Today.

Jan 1, 1962

By G Ryan, Yu Nazimova

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. This paper aims to highlight the global exploration opportunities that exist in connection with Ural-Alaskan (UA)-type intrusions. The key economic importance of UA intrusions is the existence of metallic platinum (mainly iron-platinum alloys) associated generally with chromite mineralisation and located within a dunite core, especially its coarse-grained part. Being very dense and resistant to erosion, platinum can form rich placers as the intrusion erodes. Big multimillion ounce placer platinum deposits of this type have historically been successfully mined for many years (eg Russia, Colombia and Alaska).However, large-scale exploration and mining of platinum placers currently occurs only in the Russian Far East. Outside of Russia, there is now little or no understanding of this type of deposit and its economic importance. Using successful operations in Russia as examples, it is demonstrated that there are many opportunities for similar discoveries all around the world, especially around the Pacific Rim, where such intrusions tend to be concentrated. Examples of highly prospective areas in eastern Australia and New Zealand are given. There is also excellent potential in British Columbia (BC) Canada, South-East Asia (Philippines, Indonesia, Papua New Guinea and New Caledonia) and South America (Colombia and Ecuador).CITATION:Nazimova, Y and Ryan, G, 2015. Platinum potential of the pacific rim of Ural-Alaskan-type intrusions, in Proceedings PACRIM 2015 Congress, pp 665–670 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015