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By K Sanematsu

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Ore deposits of rare earth elements (REE) in South-East Asia are classified into four types: carbonatite, allanite, ion-adsorption and placer. Occurrences of the carbonatite deposits are confined almost exclusively to the Red River Fault Zone of northern Vietnam. Since the carbonatites contain dominantly REE fluorocarbonates (eg bastnasite) and lesser amounts of monazite, they are rich in light REE but poor in heavy REE. The ion-adsorption type deposits and prospects were found in Myanmar, Vietnam and Thailand. The ion-adsorption ores generally show lower REE grades than those of the carbonatite type and placer deposits; however, they could be enriched in HREE, which are more precious and scarce commodities than LREE. The ores consist of weathered granites with a significant amount of ion-exchangeable REE, which are extracted by using a dilute electrolyte solution. The ion-exchangeable REE are likely to be sourced from REE fluorocarbonates, allanite and titanite because these minerals are relatively susceptible to weathering and release REE3+ ions into soil water. In contrast, monazite and xenotime are resistant to chemical weathering and could form placer ores. Placer monazite and xenotime have been processed as by-products of placer Sn, Zr or Ti in Malaysia, Thailand and Indonesia, although the current production is small.CITATION:Sanematsu, K, 2015. Rare earth element deposits and prospective areas in South-East Asia, in Proceedings PACRIM 2015 Congress, pp 671–678 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

Titanium tetrachloride may be reduced to trichloride with hydrogen on a hot tungsten filament and other hot: surfaces. The effect of temperature, time and size of t.he filament on the rate of reaction has been studied. A laboratory unit for preparing a few pounds of trichloride at a time is described. The yield of trichloride is 2·2 - 2·4 gm/sq. cm. of hot surface/hour at 1,000°C. and the energy requirement 3'5-4 kWh/pound of trichloride produced.'INTRODUCTIONThe lower chlorides of titanium (titanium tri- and dichlorides) are amenable to electrolysis, being electrovalent in nature. Furthermore, relative to other oxygen-free titanium salts, they are easy to prepare in a pure state and their use has been investigated to prepare titanium. The experimentaJ work described in this paper deals with the preparation of titanium trichloride by reduction of titanium tetrachloride with hydrogen on hot surfaces.REDUCING AGENTS FOR TITANIUM TETRACHLORIDEThe free energy diagram (Fig. 1) for the formation of chlorides suggests that titanium' tetrachloride may be reduced to trichloride by various reducing agents such as aluminium, zinc, arsenic, antimony, tin, mercury, silver, hydrogen, sodium, potassium and magnesium. Ruff and Neumann (1923), Thorpe (1885) , Billy and Brasseur (1935) and Seurbert and Schmidt (1892) used various metals to reduce tetrachloride to trichloride and found that the yields were invariably low and the products difficult to separate.Besides the metallic reducing agents, hydrogen may also be used to reduce titanium tetrachloride to trichloride.Goerges and Stahler (1909) obtained a deposit of violet...

Jan 1, 1956

A statistical investigation of folding at Mount Isa disclosed similar patterns in both the shales and the "silica dolomite" zones. Analysis of these patterns yields 3 groups of folds fully developed north plunging folds, fully developed south plunging folds, and flexuresrepresenting stages of development of folds. Interpretation of results indicates that a regional force from a southerly direction was responsible for the folding.The general pattern of shearing is allied to that of folding, with the exception of bedding-plane shearing. Many shears resulted from continued application of force on folds which ruptured after overthrusting. Other shears resulted from rupture of the more incompetent shale members, without associated folding. The shear pattern is consistent with the theory of a regional force from a southerly direction.INTRODUCTIONThe notes on folding and shearing presented in this paper are part of a current study of the structural geology of Mount Isa.FOLDING 1Measurement of FoldsInvestigation of folding underground involved the measurement of plunge, strike and dip of the axial plane, and the order of magnitude of each fold, together with its location and the rock type. The total number of folds measured was 701, of which 411 occurred in shale areas and 290 within the "silica dolomite" zones. All folds measured are located on main levels, from 7 level to 13 level inclusive. The sections of the mine involved are the Black Star, Black Rock and Racecourse. Detailed investigation of folds on the upper levels (4, 5 and 6) has not yet been done, but observations there suggest...

Jan 1, 1961

By Jianmin H, Shuqin L

This paper analyses problems associated with cement based technique in metal mines, and provides a new mining technique of packing the tailing sand and water into solidified material. In the new technique, the cementing agent is a solidifying material containing a high percentage of water and tailing sand. The sand and water solidify into the packed body at the same time. The slurry of the packed body varies widely in concentration and suitability for different mining conditions. It consists of two liquid materials, each composed of a cementing agent, tailing sand and water. The thick liquids are transported to the packing place at the same time. Their pumping property is good; they do not solidify or block up the pipe during transportation. At the packing place, the two liquids are evenly mixed.The mixed liquid flattens out well and its solidifying speed is so fast that it solidifies into a packed body within a very short period of time. The compressed strength of the packed body can reach 1.2-5MPa in one day, which satisfies the requirements of different mining conditions. By using the new mining technique, all the tailing sand can be used again in the packed body and it is low in cost and investment. The mechanisation is easy and thus the working efficiency is increased and the use of labour decreased. Contamination problems caused by i. Dr & Prof. Beijing Graduate School, China University of Mining Science and Technology,Beijing,China 2 Northern .Jiaotong University, Beijing,China 3. Beijing Graduate School, China University of Mining, Science and Technology

Jan 1, 1992

Until recently, nickel laterite projects have been largely ignored, due to their supposedly higher treatment costs compared with sulphides, and to their perceived processing difficulties. A number of laterite projects in the 1970s were abandoned because of high capital and operating costs, while others experienced severe technical difficulties. Conventional wisdom had it that laterites would not be exploited until most of the sulphide orebodies had been depleted. Why then, have Australian mining and exploration companies started a resurgence of interest in the treatment of nickel laterites? It all began with the Bulong project, which has been under study since 1987, while more recently two further projects, Murrin Murrin and Cawse, have been initiated and are being fast-tracked to take advantage of the current high nickel and cobalt prices. A further project in NSW, Syerston, has also been investigated at bench-scale, but no further development has yet been announced. All these projects have the following advantages: 1. Good location near a major mining centre and,reasonably close to power, water, roads, accommodation and a developed service industry. 2. Straightforward, low cost mining. 3. Low cost of acid or sulphur. 4. Good to very good cobalt credits. In addition, there have been significant technological developments in the design and operation of high pressure autoclaves and high rate thickeners, as well as solvent extraction and electrowinning technology. This has helped to decrease capital costs and technical risks, and has allowed the development of alternative flowsheets to the existing laterite operations (Taylor, 1996).

Jan 1, 1996

By Davey FJ

The Hikurangi Margin of eastern North Island New Zealand represents the feather edge of the over-riding Indo-Australian Plate at its convergent boundary with the subducting Pacific Plate. Towards the south, convergence becomes slower and increasingly oblique, and sediment supply from the Southern Alps becomes increasingly rapid. In this environment a 150 km wide, imbricate thrust, accretionary prism has grown since the Miocene, uplifting slope ridges and basins and a range of coastal hills. Offscraping of thick, axially transported, trench-fill turbidites begins in a zone of proto- thrusts, which extends up to 25 km beyond the principle, slope-toe, deformation front. On the slope, landward tilted, trench-slope basins are separated by ridges. The ridges ride up on thrusts that sole out at a major decollement. The decollement dips landwards at 3 degrees to a depth of 14 km at the coast, where it coincides with an onshore zone of high seismicity. Beneath the decollement, about 1 km of consolidated, oceanic sediment is going under the margin with the underlying oceanic basement. Some of these sediments may underplate the frontal ranges to the west and geochemical evidence of subducted sediment is found in the volcanic zone beyond. A rapid decrease in the width of the accretionary prism to the north is associated with a decrease in sediment supply and perhaps with a dislocation in the downgoing plate. To the south, the accretionary prism narrows, swings westward, and merges into the zone of very oblique collision that marks the transform between mirror image subduction to north and south of New Zealand.

Jan 1, 1987

By J Safarian, M K. Kar

Bauxite residue is one of the most important by-products from the alumina industry with no commercial use till now. The utilisation of bauxite residue through pelletising with different lime additions, hydrogen reduction, and smelting has been studied in this work. Three different types of green pellets were made with varying calcite-to-bauxite residue ratio and subsequently sintered at elevated temperatures. The sintered pellets were isothermally reduced at 1000°C under hydrogen gas followed by smelting of the reduced pellets in argon at 1500°C. Smelting of the reduced pellets leads to the recovery of metallic iron and the formation of a leachable calcium aluminate slag. X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to characterise the phases and microstructural analysis. The iron produced in the smelting process has a high purity, above 99.5 wt per cent. While the iron content of the slags is quite low, and the slags shows variations of krotite (CaAl2O4), gehlenite (Ca2Al2SiO7), and perovskite (CaTiO3) phases based on the variation of calcite addition. It was found that the more calcite addition in pelletising yields higher percentage of krotite phase as compared to lower calcite-containing pellets. Employing quantitative XRD analysis, the krotite phase fraction was found approximately 85 wt per cent for higher calcite-added pellet, and around 74 wt per cent for lower calcite-added pellet. FactSage™, ver 8.1 (Thermfact and GGTTechnologies) thermodynamic software was used to evaluate the obtained experimental data, they both revealed that the

Jun 19, 2024

In the last two decades, equipment used in the coal mining operations has become much more sophisticated. The way that work is organised and performed in the industry has also changed significantly. Changes in equipment specification or procedures inevitably means that the risk associated with that equipment or procedure also changes. In an attempt to address this the Joint Coal Board Occupational Health and Safety Trust (JCB) commissioned the University of New South Wales Mining Research Centre and Mine Site Technologies to perform a feasibility study into the development and deployment of Virtual Reality (VR) based training simulators in the New South Wales coal industry. The main aims of the study were to identify, the key providers of VR Technology, the VR options available to the JCB and the information that would need to be included in any simulator. It was anticipated that a critical assessment of these components would produce a format for a cost effective, state of the art simulator that could be readily accessed by all mines. The expectations of the feasibility study were that VR should offer three-dimensional (3D) simulations that are interactive, high-resolution models of real environments based on best practice Safety Management Plans. It was anticipated that the simulations would allow trainees to experience the consequences of poor decision-making and allow them to learn from their mistakes in a safe and forgiving environment. It was envisaged that such simulators would become an addition to the existing training methods used in the industry.

Jan 1, 2003

By M Robotham

In April 2013, Rio Tinto Kennecott Copper’s (RTKC) Bingham Canyon mine experienced what is arguably the world’s largest ever in-pit slope failure. The failure initiated along a major, continuous, low-strength bedding fault, named the Manefay bed, and comprised approximately 145Mtonnes of rock and waste dump material. Initial East wall slope deformations were detected some months prior to catastrophic slope collapse by RTKC’s slope monitoring systems. However, the failure mechanism was different to that which had historically been experienced in the prior more-than-100 years of open pit mining. Failure occurred as two separate events, the initial one likely consisting of a frictional failure of rock materials along the Manefay bed itself, before a second phase of failure occurred, which included a large mass of old rail dump material. The combination of these events led to a much larger failure run-out than had been anticipated by the RTKC team which led to loss of, and damage to, mining equipment and infrastructure as well as significant interruption to mining activities. Due to the diligent monitoring of the slopes no safety impacts were experienced at the mine, and as such the details and learnings from this failure can readily be shared with the broader mining and geotechnical industries to avoid similar recurrences elsewhere. This is an extended abstract only. CITATION:Robotham, M, 2018. Bingham Canyon Mine – from adversity to excellence, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 3–4 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

By S Cossfo Torres

Minera PenmontÆs gold mine, La Herradura, is located at the northwestern Mexican state of Sonora and consists of an open pit mine and heap leaching facility for the recovery of gold. The production began in July 1998, and today La Herradura produces about 200 000 oz of gold per year. Standard sampling and assaying protocols were established during exploration based on heterogeneity tests. However, at deeper zones of the pit, coarse gold became evident and it was necessary to develop a new sampling protocol in order to minimise the fundamental error and improve the metallurgical accounting. This new sampling protocol requires cyanide leaching the whole pulverised sample from the blasthole, assaying pregnant solution and fire assaying 50 g of tailings. A sampling study was performed on 195 blasthole samples analysing gold under the standard and new protocols. The new protocol demonstrated that the original one underestimated gold grade by approximately 27 per cent, with impacts on ore misclassification and metallurgical accounting. According to the ore grade control system, mineral with gold grade above 0.35 g/t was sent to the leach pad and mineral with lower grade was classified as waste. Based on the sampling study, it was decided to classify a low-grade ore with gold assay between 0.20 and 0.35 g/t which was stored for future treatment under better gold prices or should mine production decrease. These two conditions were present during 2005 and 2006, when about 3.5 Mt of low-grade ore were leached.

Jan 1, 2008

The Archean Gossan Hill Group at Golden Grove, Western Australia, hosts two potentially economic volcanogenic massive sulphide deposits. The volcanic-sedimentary succession hosting this mineralisation is composed of a facies association which includes the products of rhyodacitic to,andesitic effusive volcanism, mass-flow sedimentation and concentrated hydrothermal fluid discharge, in a deep subaqueous setting. The Tertiary Kuroko deposits of Japan are widely compared to Archean volcanogenic massive sulphide deposits and a comparison of the facies associations hosting this style of mineralisation, in these two successions separated widely in time, allows a refinement of facies models suitable for exploration in ancient successions. The required deep subaqueous environment for the formation of volcanogenic massive sulphide deposits places constraints on the physical processes that can operate during accumulation of the host stratigraphy. Limitations on the operation of physical processes is reflected by the resultant facies association which can be used to characterize suitable volcanic-sedimentary successions in which volcanogenic massive sulphide mineralisation may be present. The facies association includes: (1) proximal effusive volcanic products - lavas and associated autoclastic breccias (2) distal volcanic products - mass-flow resedimented pyroclastic debris (3) background sedimentation - reworked volcanogenic and terrigenous mass-flow sediments and (4) chemical sediments - exhalites including cherts, sulphides and oxides, with perhaps various carbonates and sulphates. Primary pyroclastic deposits are not expected to be present, other than distal water-lain air-fall deposits, derived from shallow to emergent basin margin explosive volcanic centres, which also provide a source for the resedimented pyroclastic debris.

Jan 1, 1987

By M I. Pownceby, M A. Rhamdhani, S Purohit, G Brooks

The use of concentrated solar flux for high temperature metallurgical applications is a wellresearched area with several reported literatures on solar calcination and metal oxide reduction. This paper presents two such processes with potential to reduce the carbon footprint from ironmaking through using concentrated solar flux. The first process involves solar flux incorporation to the recently developed lime-magnetite pellet (LMP) route of magnetite ore agglomeration. The second process is a hybrid solar-smelting route for iron ore-coal composite pellets that utilises solar flux to provide process heat. Both the concepts of solar agglomeration and solar smelting process were investigated using a solar simulator-hybrid reactor set-up at Swinburne University of Technology. Results from solar agglomeration experiments at 950°C suggested no change in the reaction mechanism of the LMPs under solar irradiation compared to electrical heating. The percentage and morphology of the primary phases (mainly CaFe3O5) appeared similar for both solar and electric heated LMPs. The solar-smelting of magnetite concentrate-lignite coal composite pellets at 1130°C showed a maximum metallisation of 55 per cent after 1.5 hrs of reaction. The solar-smelt process has about 25 to 35 per cent lower CO2 emission compared to the blast furnace ironmaking. Technoeconomic analysis of implementing a CST facility in an existing composite pellet process suggested a payback period of about ten years at a heliostat cost of $A100/m2 and natural gas cost of A$10/GJ. The economics of CST implementation can be further enhanced by decreasing the thermal losses from the heliostat field and reactor.

Nov 8, 2021

By A McRae

Much of western New South Wales is characterised by an extensive regolith formed during more than 60 million years of exposure, weathering and erosion. This cover includes intensely weathered in situ regolith and superimposed transported materials of variable thickness, commonly in complex palaeochannel systems. Mineral exploration in this region has been considerably hampered by the cover, which can complicate or maskgeochemical anomalies and also obscure geophysical signatures. A detailed multi-disciplinary study of part of this region, centred on the Cobar-Girilambone area has demonstrated a methodology for exploring through this regolith. The approach involves regolith-landform mapping to establish the main landscape and palaeolandscape elements and to determine the nature and spatial occurrence of different regolith materials. By combining knowledge of the surface distribution of different regolith-landform units with available 3D information on the regolith and geophysical data it is possible to construct simplified derivative maps or exploration ægoÆ maps, which can be used to advise appropriate exploration strategies or help interpret acquired exploration data. This study has also established the major regolith controls on geochemical dispersion and determined key background element associations. These regolith-related element associations can result in highly variable background levels for many trace elements and need to be understood and factored into the analysis of geochemical data for different regolith sampling media. With better knowledge of the regolith it is possible to select the most appropriate exploration techniques and sampling media for a given area, as well as apply appropriate normalisation procedures to the acquired data. Exploration success can be greatly improved by using many existing techniques in æregolith smartÆways.

Jan 1, 2004

The ore deposits investigated are composed primarily of hcmatite and can be grouped into three categories depending on the amount of leaching of silica and carbonate which has occurred from the original iron formation, and on the amount of recrystallization of the hematite. Minor constituents are magnetite. goethite, and quartz.Texturally. there are five different types of hematite, formed at different stages during the genesis of the ores.These are1. anhedral hematite grains formed by recrystallization of hematite already present in the original iron formation.2. hematite formed by martitization of euhedral magnetite, 3. massive aggregates of fine- to medium-grain hematite formed by recrystallization of (l) and (2).4. tabular or prismatic hematite grains occurring around the boundaries of the massive aggregates or martite euhedra. and in fractures and5. specular hematite. which is present in fractures in ore types (l) to (4).Minor and trace-element analyses, determined using an electron-probe microanalyser. indicated that only silica (less than 0·01 per cent) and cobalt (less than 0·002 per cent) were present in the magnetite and hematite from unaltered iron formation and in the hematite from the ores. Low concentrations of trace elements are typical of magnetite in ores formed as marine precipitates. On the basis of the analyses alone. it proved impossible to distinguish between the five hematite types. A determination of the variation in rare-earth trace element contents between iron oxides in the iron formation and iron oxides in the ores indicates that the rare earths were depleted during ore formation. A possible explanation is that they were removed in solution with silica as it was leached from the iron formation.

Jan 1, 1971

By P K. Seccombe

The McKinnons gold deposit is hosted by weakly deformed, Palaeozoic metasedimentary rocks of the Cobar Basin in the western Lachlan Fold Belt of New South Wales. Mineralisation comprised a largely supergene resource of 1.7 Mt of ore, grading 1.7 g/t gold, established over structurally controlled, primary gold and base-metal mineralisation in underlying, carbonate-rich meta-siltstones and sandstones of Early Devonian age. Mineralisation was associated with at least two major fluid cycles. The first cycle was characterised by four stages of vein formation. Early quartz and carbonate veins (Stages 1 and 2) and quartz-pyrite breccias (Stage-3) occurred prior to, or early in, the main regional deformation (D1). Continued D1 deformation produced syntectonic, carbonate-base-metal veins (Stage-4), primarily in dilatant zones adjacent to fold axes. The second cycle of mineralisation was an epithermal-style event, driven by a shallow, syn-D2 or post-tectonic intrusion, defined by aeromagnetic imaging. The intrusion may have exploited a jog, controlled along the basin margin by basement faults. Mineralisation produced gold-pyrite veins, associated with pervasive quartz-sericite-adularia and chlorite-sericite alteration. Highest primary gold grades are confined to quartz-adularia boiling zones. The McKinnons deposit offers an important example of mineralisation formed by multiple processes. Early-stage, base-metal mineralisation at McKinnons reflects structurally focussed, basin dewatering and metamorphic processes, typical of other deposits in the Cobar Basin. By contrast, late-stage gold mineralisation at McKinnons is magmatically driven and of epithermal style. Recognition of overprinting distinctive geological events is critical, not only in modelling ore formation, but in developing a versatile exploration concept.

Jan 1, 1999

On the 18th November, 19'58, the first coal was delivered to the Morwell Power Station from the adjacent Open Cut using conveyors for the transport of the coal from the working face to the boiler bunkers. As the cut develops the coal seam will be worked for its full depth of about 360 feet from four benches, each feeding a conveyor line along th.e face and up out of the cut to the power station and briquette factory. By 1970 the estimated maximum daily demand reaches 60,000 tons and the total annual output 18 million tons. The complete conveyor installation will then total some 9 miles with a capital cost of over £3~ million.The choice of conveyors in place of the more usual rail system was made possible by the development of movable belt conveyors which use mechanical conveyor shifting, high belt speeds and flexible high strength belts and the paper deals with these and some other aspects of the scheme.INTRODUCTIONThe development of brown coal deposits is usually based on open cut workings equipped with a few large dredgers giving an almost continuous output of coal or overburden which has to be hauled a comparatively short distance. These are ideal conditions for conveyor operation, and it is surprising that, until recently, rail transport has been used almost exclusively in brown coal open cuts. In some cases inclined conveyors have been introduced to take the coal from the coal levels up out of the cut to bunkers at groundlevel, but trains have been left to operate between the ditch bunker feeding the conveyor system and the dredger.

Jan 1, 1960

By P Gnnther, A M. van Niekerk

Coal mining operations in the Upper Olifants River Catchment in the Mpumalanga Province of South Africa are challenged with the increasing production of excess mine water that cannot be fully managed by existing practices of pollution control at source, recycling, and reuse on mining sites, storage and limited release to the natural water course. In contrast to this, the Olifants River Catchment is experiencing water stress and insufficient water is available to satisfy all water quantity and quality requirements for future industrial and municipal growth. It is estimated that the catchment has a deficit of 192 million m3 per annum if the reserve water requirements are taken into account. The future increased water requirements can be met by water transferred to the Olifants River Catchment from adjacent catchments. The cost of transferred water is likely to be substantially higher than the current cost of water supplied to local municipalities, commerce and industry. BHP Billiton and Anglo Coal Corporation are working together to jointly implement water management strategies that will contribute to the achievement of in-stream and dam water quality and aquatic objectives for the catchment. Consideration is now being given to the treatment and beneficial use of excess mine water. This will inaugurate a new era for the coal mining industry in South Africa, in which a pollution threat to the water resources in the Upper Olifants River Catchment is converted into a water source for beneficial use. Three potential mine water reclamation and reuse schemes have been identified and this paper details the technical, institutional, legal and financial considerations in the implementation of these schemes.

Jan 1, 2006

By T Jones, K Karunaratna

The Kalgoorlie Consolidated Gold Mines (KCGM) Fimiston Open Pit is located on the eastern boundary of the Kalgoorlie-Boulder City and is mining an area traditionally known as the Golden Mile. The pit area has been continuously worked since 1893, predominantly by underground mining methods and more recently through open cut mining. There are over 2000 km of old mine headings and numerous stopes under the open pit area. KCGM has interpreted and digitised the underground mine plans and stope sections into a common database. A 2D-model software package, called Pits, was developed in-house and allows old workings to be displayed at any bench level; this is integrated with 3D Vulcan modelling software, which allows triangulated surfaces to be displayed. Almost every mining activity is affected by underground workings. The effective management of the interaction between current mining and the underground workings is very important for safety and production. A specific ævoidÆ management department has been formed and its broad objective is to minimise the impact of underground workings upon production while maximising safety. Special criteria and procedures have been developed and implemented to keep personnel and machinery from being exposed to unsafe ground. It is of primary importance to accurately define the location and outline of underground workings in advance. Probe drilling has been used as the key tool for that purpose. Various geophysical methods have also been trialled on site to detect underground workings; these are discussed in some detail. This paper discusses ævoidÆ management issues such as data integration, void detection and flagging. The impact of underground workings on mine planing, production and slope stability is also discussed.

Jan 1, 2003

By Horiszt G

his report is going to point to that the effect of the mining dewatering on the area of Transdanubian Mountain Range has reached a phase when the cost of dewatering and providing damages can seriously jeopardize a profitable mining operation. Up to 60s the interest of mining had been dominant only, but since the begining of 80s the conceptions of industrial development and the value of enviroment protection have been changed. The natural karstwater balance of the TMR can be presented (Figure Land 2.) and the present situation of it points to that the descharge has exceeded the reacharge in 50 %. During the past 10 years the decreasing of the stored karstic water resourches was 1.1 km . The decreasing of the spring yields reached 80-82 % of the natural ones. (Figure 3-4.). Conservation of the present discharge may lead up to the totaly drain of the karstwater regime. A computer aid control system had been to develop by the bauxite mining and using of it the yield of dewatering decreased and a moderate rising of the water table has started since 1986. A recunstruction was made at the biggest thermal-medicinal lake its springs have had their source in 40 meter depth inside a spring cave at the bottom of the lake. Earlier the spring yield decreased due to the dewatering activity of mines. As a result of using of the CAC system and the providing works at the thermal sprino,the karstwater balance has got in the state of equilibrum, the first cost was decreased and spring yield was increased and the enviromental limits were adverted from the way of mining.

Jan 1, 1988

By d&apos, Alton AJ, Rigden DT

Modern petroleum refining offers a complexity of environments, each requiring different metals for the satisfactory performance of-the various sections of the refinery, and this paper first outlines the varied enva.x¦on-ments thus met.It follows that the metal types in use will also vary to suit each particular environment, and the paper' consequently covers the use of ferrous-metals, ranging from plan carbon steels to the high alloy types and the non-ferrous metals, particularly copper and its alloys.The failures of some,of these metals and alloys are then illustrated by experiences it Kwinana. These failures are duo to (a) corrosion, (b) erosion, (c) faulty welding, and (d) mechanical defects,' of which the first is by far the most prevalent. The protective measures taken to prevent subsequent failures are then given under one or other of the following headings :(1) alterations in process conditions, (2) the use of alternative ,alloys,(3) suitable heat treatment, (4) redesign of the failed section, (5) cathodic protection, and (6) use of corrosion inhibitors.Reference is then made to the use of specialised metals and alloys.Metals, generally in the form of oxides or salts, are also used as catalysts in refining processes. Activated alumina is used, combined with silica .forScracking' of heavy oils, and as a support -for platinum, cobalt, molybdenum, nickel and similar metals, which catalyse hydro-genation and dehydrogenation-processes. .In the final formulation of petroleum products metallic compounds may be added. Reference is made to the large quantities of lead used by the petroleum industry and to the use of metallic soaps and detergents in the formulation of lubricating oils and greases.

Jan 1, 1962