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By P. Danson, D. A. White, S. Bashir

Composite ion exchange materials made of SnO2, TiO2 and MnO2 can be used to remove radioactive contaminants from nuclear waste streams. In several cases their selectivity and capacity are enhanced by mixing hydrous silica into the matrix. MnO2-SiO2 materials are especially useful for a number of reasons, such as their selection of heavy elements over caesium. Distribution constants and determinations of exchange capacities show that in many instances the properties of the composites are better than those of the oxides alone, while the presence of a chelating agent has been found to reduce the uptake of nuclides considerably. Methods are being developed for the bulk manufacture of the materials. Further work on sorption mechanisms is required to explain anomalous results, particularly the variation in exchange capacity for different elements and the ability of the oxides to sorb colloidal material in alkaline solution.

Jan 8, 1992

By Fergusson E.

An account is given of the history and operation of the Straits Tin market and the Penang price. The procedure by which the official ruling tin price is determined is presented and the way in which bids are treated is outlined: the price declared in Penang is the result of a joint operation by the two Malaysian smelters and is arrived at by finding the highest price at which the whole of the day's offerings for sale can be sold, thus reflecting the marriage of the offerings of the individual mine producers with the demand for Straits Tin from the consuming countries of the world. A system of accurate weighing, sampling and assaying of concentrates delivered to the smelters' premises enables the various ore-buying agencies of the two smelters to notify their central offices promptly of the estimated tin content of the concentrates their customers wish to price that day, so that by 11.00 a.m. both smelters will have exchanged with each other figures giving the total quantity of metal they have for inclusion in the day's market, at the same time exchanging particulars of the bids they have received. Miners are encouraged to sell regularly for cash and an evenness is thus achieved which avoids large daily fluctuations in overall quantity.

Dec 30, 1971

By S. V. Shiraishi, H. B. Bell

Report of discussion at February, 1971, IMM general meeting (Chairman: M. J. Cahalan, President) of a paper published in Transactions/Section C (Mineral Processing & Extractive Metallurgy), vol. 79, June, 1970, pp. C120-C127, with a contribution by Wright P.A. on the miscibility gap

Dec 1, 1971

By I. Garba

The Bin Yauri deposit in the Zuru schist belt of northwestern Nigeria is a vein-type quartz-sulphide-carbonate gold mineralisation hosted by a brittle fault zone. The occurrence of the mineralisation in a contact zone of a Pan-African granitoid was believed to be sufficient evidence of deposition from magmatic fluids. However, studies may now indicate a metamorphic source for the mineralising fluids. A study of rare earth element geochemsitry was used to investigate the nature of the fluid-rock processes involved and identify the sources of the auriferous mineralising fluids.

Jan 12, 1992

By J. Gough M. D.

There are many points still obscure regarding the nature of coal-workers'- pneumokoniosis, but the interpretation of the disease has been greatly clarified in recent years. It is now known that exposure to fumes or gases or other conditions peculiar to coal-mining are not necessary factors in the production of pneumokoniosis. The same disease occurs in coal-trimmers working in the docks, and it is thus established that the inhaled dust is the primary factor. On the other hand, there is no completely satisfactory explanation of the distribution of the disease. Geological and petrological studies have not given an unequivocal explanation of the difference in incidence in different parts of the coalfield. It is an open question whether the quantity of dust inhaled is more important than its chemical composition. However, there is ample evidence from the medical side that elimination of dust and of tuberculosis from the environment of coal workers will be required to prevent pneumokoniosis. Much is being done with regard to elimination of dust, and a similar energetic action is required in regard to tuberculosis.

Jan 1, 1947

By E. A. Brocchi, D. H. Gameiro, P. K. Jena

Carbon tetrachloride was found to be a very efficient chlorinating agent for anatase concentrate, even at the low temperatures that were investigated (250-400 degrees C). For example, at 400 degrees C about 90% of the anatase concentrate was found to have been chlorinated within 60 minutes

Jun 13, 1905

By R. H. . T. Garnett

Contributed remarks on paper published in the Transactions, Mining industry section, vol. 100, September- December 1991, A121--45

Jan 12, 1992

By T. Guyaguler

An analytical technique using computer-based multiple-regression methods was employed to determine the relation between the dust-producing index and inherent rock properties of typical samples from a coal-producing area, one of the aims being to provide a preliminary predictive tool for practical use. The investigation demonstrated that factors varied in their influence under different conditions, the brittleness:toughness ratio and the hardness being the most significant inherent properties with hardness showing the highest positive correlation coefficient

Jun 13, 1905

By P J. Borrington

Offering 1000 hour salt spray protection, the KEYCOAT 1000 coating presents no chipping, cracking or deformation when hammered or flexed through 90 degrees or more. This cost-effective metal protection system features lubrication performance equal to molybdenum disulphide and Poly Tetra Fluoro Ethylene (PTFE) grease providing complete anti-seize protection whilst aiding assembly and disassembly. In addition, the coating is impervious to acids, alkalis, solvents and attack by oils and all fuels. KEYCOAT 1000 has been exhaustively tested in three main industry sectors - automotive, heavy earthinoving vehicles and chemical - where it lias been proven to outperform conventional systems in all respects and as the film formed is less than one thousandth of an inch thick (typically 20 microns), it rarely presents the engineer with any tolerance difficulties. KEYCOAT 1000 is one of a w ide family of products which offer protection and lubrication to a wide industry base, from aerospace to food and with temperatures ranging from minus 190 C to plus 30 C.

Jan 4, 1997

By K. El-Barawi, Hussein M. Kamal

Chlorination was performed of iron-rich chromite ore from Barramyia, United Arab Republic (UAR), together with its concentrate. The effects of change of grain size, chlorine gas flow rate, time and temperature were studied. The extent and mechanism of chlorination were followed through chemical and structural analyses of the feeds and complete chemical analysis of the chlorination products. By conducting the chlorination process for short periods at 600°C or lower temperatures, products having high Cr-Fe ratios suitable for ferrochrome production can be obtained.

Dec 1, 1971

By T. Guerin

More than 370 million litres of oil leak from hydraulic equipment every year, excluding all other sources of plant fluid losses. This item analyses the causes of fluid spills from plants and equipment on resource construction sites, and offers some possible solutions.

Apr 1, 2015

Papers submitted at the 8 ordinary general meetings are listed and details given of the proceedings of the annual general meeting held on 20 May 1971

Dec 1, 1971

By R. Trueman, D. B. Tyler

Numerical modelling was used to determine the magnitude and direction of stresses around drives both adjacent to and distant from open stopes in the South Crofty tin mine. Modelling predicted that drives near the stopes are situated in a stress-relaxed zone. The peripheries of drives that are sited in solid rock away from the influence of stoping are in compression. Key-block modelling was used to determine the typical geometries of critical blocks and distinct element modelling was used to determine block stability. The conclusions derived from modelling fitted the observational data. This indicated that key-block theory is a valid tool for analysing the stability of roadways in the South Crofty mine. The support requirements for drives located next to stoped-out areas were formulated using a risk analysis approach to key-block formation. The results were compared with support guidelines derived using empirical design methods. Good agreement was obtained for the roofs of the drives but not for the sidewalls. The concept of a critical excavation width was formulated: once an excavation is larger than the critical size the length of rockbolts need not be increased as the excavtion dimensions increase. This may be the case in all rock mases.

Jan 4, 1993

By A. C. Dunham, Y. D. Drakapoulos, P. W. Scott

The Pt and Pd occur alloyed with copper in small, irregularly-shaped grains, 0.25-5.0 micrometers in maximum dimensions. Grains of unalloyed native copper are also present. The grains are completely surrounded by or marginal to magnetite with inclusions of Ni-Fe-Co sulphides and native Ni-Fe, which is apparently a product of the serpentinisation process. Crystallisation of the Pt-Pd-enriched copper probably occurred at the same time, at low temperature, but the previous form of the Pt and Pd is unknown as no earlier PGE phases have been found. While Pt and Pd minerals are usually important in early-magmatic base-metal sulphides, Pt alloyed with Cu is extremely rare and apparently occurs only very late in the paragenetic sequence. A Cu alloy with Pd dominant over Pt and only minor amounts of other elements appears not to have been reported

Jun 14, 1905

By A. Policard

The question, of the pathogenesis of pneumokoniosis is very important not only from the social and economic points of view but also from the purely biological. The study of the pathogenesis of the disease leads to fascinating problems of cytology and cytochemistry. Two problems present themselves for examination from an analytical and critical point of view: 1. The first reactions of the alveolar walls to inhaled dusts. 2. The precise nature of the action of mineral dusts.

Jan 1, 1947

By H. B. Bell, L. C. Smith

Measurements have been made of the activity of 'FeO' in 'Fe0'-Mn0-Ti02 melts at 1475 degrees C. The results obtained are discussed in terms of ideal mixing of titanates and in terms of a regular solution model. On the basis of the regular solution model activities of Ti02 and MnO in the Fe0-Mn0-Ti02 and Mn0-Ti02 systems have been derived. The data have been shown to be consistent with the liquidus lines in the phase systems. Examples are given of the application of the data to slag-metal equilibria, being used to derive slag-metal data between liquid iron and Fe0-Mn0-Ti02 slags

Dec 1, 1971

By R. P. Foster, ed.

The short selection of papers in the special issue provides an insight into the level of exploration activity in Africa and the science and technology that are underpinning it. A country-by-country survey is followed by discussion of geochemical exploration in tropical soils, the Liptako region of Niger, structural styles of deposits in Zimbabwe's Bulawayo-Bubi greenstone belt, structural controls in Zimbabwe's Eldorado shear zone, the regional framework for deposits in the Odzi-Mutare-Manica greenstone belt of Zimbabwe and Mozambique, and the Iperindo deposit in Nigeria's Ilesha schist belt

Apr 1, 1996

By R. G. Jones

Many novel projects suffer delays, cost overruns or failure because of inadequately qualified technologies. A new qualification to measure the quality of innovation is discussed.

Jul 1, 2015

Jan 1, 1947

By NA NA

RJB completes purchase of second lease-licence mine, Miller buys Wimpey Mining, Point of Ayr Colliery in North Wales closes, jobs created at Lithgow Minerals Processing Park, Australia.

Jan 9, 1996