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By Armstrong RW, Middlin B

The development, design, construction and operation of the new Solvent Extraction/BCA process plant at Copper Refineries Pty. Ltd., Townsville is described.The process offers substantial savings in electrical power costs, improvements in plant hygiene, and a lowering of materials handling costs compared with conventional electrowinning technology.The solvent extraction process extracts arsenic from copper Tank House electrolyte using a tributyl phosphate (TBP) - kerosene solvent. The plant incorporates fourextraction stages, two scrub stages, and three stripping stages to produce an arsenic-bearing low-acid strip liquor. This strip liquor is mixed with copper sulphate, and neutralized with ammonia to form a copper (II) arsenic (V) crystalline product, bicupric arsenate (BCA). This product is then used in the manufacture of chromated copper arsenate timber preservatives (Royston 1982).

Jan 1, 1985

By Yanmin Wang, Eric Forssberg

This paper presents recent experimental results in wet ultra-fine grinding and classification of industrial minerals carbonates and kaolin clays using a stirred ball mill and a high performance centrifuge. The studies have been focused on the effect of beads (size, density and load) on the grinding efficiency. The use of chemical additives for the control of slurry rheology in the stirred ball milling is presented. The role of pre-crushing with a high-pressure roller mill on subsequent ultra-fine grinding is discussed for energy saving and size reduction. The use of a disc-stack nozzle centrifuge for ultra-fine classification duties at high solids contents is presented.

Jan 1, 1998

By Mark Cadzow, Rodney Lamb

CARBAD is a recently developed Australian process for the recovery of gold and platinum group metals (PGM). The process relies on the selective agglomeration phenomena of the gold and PGM to capture the mineral in a carbon-hydrocarbon media. The precious minerals are then extracted from the loaded media by a solvent gold room process producing a relatively pure concentrate. The media is then reformed and recycled. The process development from batch test work to a 5 t/h commercial scale CARBAD plant is discussed. The operation and results of processing a variety of ore types at several alluvial and hardrock gold mines is examined. The operating and capital costs for the CARBAD process shows that it is significantly less than that the conventional CIP/CIL. The environmental safety of the process is a major feature where precious metal deposits are located within urban environments or within wilderness areas.

Jan 1, 1989

By Ilkka V. Kojo

This paper gives an overview of the primary copper smelting business during the years of flash Smelting in the light of various projects taking into account the sustainability of copper production. Also the future challenges of copper smelting are addressed with special emphasis on the environment. Flash Smelting connected with either Peirce-Smith converting or Flash Converting offers the most economical and environmentally friendly alternatives for the smelting of normal and lean copper concentrates. For rich copper concentrates the feasibility of Outokumpu Direct Blister Flash smelting is, understandably, beyond compare. When the total investment costs for building a smelter and acid plant are considered, it is clear that Flash Smelting is the more feasible option compared to bath smelting. Reduction of equipment and operating cost is further achieved by the LUREC-process developed by Outokumpu Technology for operating plants with SO2-contents up to 25 % by volume. As an example the Kennecott-Outokumpu Flash Converting Furnace (FCF) has been in operation at Kennecott Utah Copper for 10 years and has achieved excellent results both environmentally and production vice. The FCF treats the entire output of the Kennecott Flash Smelting Furnace and has excess converting capacity. Furnace life, initially projected at two to three years, is now projected to be more than 5 years. It is likely the life will be essentially the same as a well-operated Flash Smelting furnace.

Jan 1, 2006

By M. M. Fine

Normally the U. S. produces less than 10 pct of its annual manganese requirement. About 95 pct of domestic consumption is used by the steel industry.1 The strategic and critical nature of manganese has been recognized by its inclusion in the national stockpile and by intensified research directed toward cataloging and evaluating domestic manganiferous deposits. The USBM has participated in these activities for many years with field and laboratory studies to assess the extent and potential utilization of domestic manganese ores. One area of particular interest is in the vinicity of Batesville, Ark., where deposits have been mined since 1849 for both manganese and ferruginous manganese ores. Production is centered in Independence County, but deposits are also found in Sharp, Izard, and Stone counties in north- central Arkansas. Miser has described the geology and manganese mineralization in some detail.2,3 The rocks of the area are sedimentary, consisting of sandstone, limestone, shale, and chert. The two formations of greatest importance,4 Fernvale lime- stone and Cason shale, are host rocks of the primary manganese mineralization.

Jan 8, 1959

By M. Taxiarchou

The continuously increasing rate of the non-renewable raw material consumption together with the production of immense volumes of solid wastes and effluents is one of the main characteristics of our modern society. This leads to an unconditional necessity to reduce the raw material and energy consumption and to recycle the used materials and products. Life Cycle Analysis (LCA) constitutes a promising tool in this direction. LCA is a methodology, whose main purpose is the objective calculation and analysis of the environmental burdens of products, processes and activities as well as the estimation of the possibilities to perform environmental improvements in combination with the rational use of raw materials and energy. The purpose of this paper is to present the life cycle of marble and granite from the quarrying to the processing stage, including the transportation between the quarry and the processing plant, by quantifying the environmental impacts that derive from each stage and the evaluation of their potential effects to the environment and to human health.

Jan 1, 2007

By Joseph William Pinder

Every millman engaged in the operations incident to the handling of crushing-rolls knows that in ordinary practice, when fine product is desired, the ore-materials delivered to the machine, divided into four sizes, may be estimated, approximately, as follows : Per cent. Papsing a 4-mesh screen,..40 2- " " ........30 " 3/4-inch-mesh screen,.. 20 Larger,...........10 This estimate refers more particularly to the requirements of medium-sized rolls and fine crushing. But, depending largely on the character of work to be performed, the coarser material is often larger and of a greater percentage, while the bulk is always more or less fine.

Jan 1, 1899

By P. K. Kaiser

A rational approach for the design of fully grouted bolts in underground excavations is presented. An analytical model involving elasto-plastic concepts and the mechanics of bolt/ground interaction was developed and tested by comparison with laboratory tests and field measurements. The theory elucidates the influence of shear stress distribution, bolt pattern and geometry on tunnel convergence. Laboratory simulation has provided convincing evidence to support the theoretical predictions. A dimensionless bolt efficiency parameter is introduced as a design tool that relates the reduction of tunnel convergence to the bolt length and density. Its application in practice is highlighted by the analysis of one case history.

Jan 1, 1987

By Jonathon M. Hanson, John F. Schatz

A combined theoretical and laboratory test program is described with the purpose of providing a useful model of the multiple radial fracturing process. A non-quantitative conceptual model is developed as the basis for detailed mathematical modeling and test planning. The model includes borehole pressurization, flaw rupture, and gas- driven fracture propagation phases. The laboratory tests are carried out in blocks of scaled rock simulant loaded to a true three-dimension stress state and with miniature propellant/explosive charges in a wellbore as the fracturing energy source. The conceptual model, fracture initiation modeling, and laboratory test setup have been completed and are described. The remaining work is ongoing

Jan 1, 1986

By M. S. Klima, P. T. Luckie

Interfacing new or improved unit operations SUBMODULES with the EXECUTIVE of a macro analysis simulator usually requires modification of the input data. For example, particle processing SUBMODULES that are sufficiently general in nature to provide useful predictions require input data for rather narrow size fractions. Such data is not always available for the EXECUTIVE and must therefore be generated by the SUBMODULE. A successful interface to allow incorporation of a new SUBMODULE for comminution and one for classification in a general stream state flowsheet simulator is presented. The general nature of the SUBMODULES, as well as the logic of expanding and contracting the required data input is discussed.

Jan 1, 1983

By Gemuts I, Hudson D. R

Massive sulphide mineralisation at the Miriam prospect, near Coolgardie, Western Australia, is fracture-controlled and associated with disseminated sulphides near the basal contact of an ultramafic lens. The lens is peridotitic in composition with a pyroxenitic zone at its base, and lies within a sequence of altered high-Mg basalts and pillowed tholeiitic basalts. Recrystallisation of the ultramafic rock has resulted in the development of secondary olivine. The average composition of the sulphide fraction of massive ore is Cu = 4.4%, Co = 0.3%, Ni = 23.0%, Fe = 31.8%, S = 40.6%, consisting of the supergene assemblage violarite-pyrite to a depth of 210 m.

Jan 1, 1973

In order to formulate appropriate and useful education and training policies and practices, it is crucial to firstly consider the demographic environment of our workforce-and the direction in which it is (known to be) heading. We can predict with a degree of certainty, that the role and influence of training on the future survivability of organisations will- become increasingly critical. This will be particularly relevant for those industries and organisations which are technologically based. The ad-hoc use of training is and, will no longer be appropriate. Organisations must move toward the on-going use of a dynamic education and training strategy based on an effective staff development programme, which meets the short and medium term needs of the organisation. The Technisearch approach is based on maximizing the efficacy of training and learning. The package provides.a total service to meet clients training needs using educational techniques geared to adult learning. it stresses the importance of ongoing research into industrial adult training and its effectiveness in improving skills and productivity. Current research on roles of supervisors in the Australian workplace and the development of the Supervisory Behaviour Questionnaire. (SBQ) indicates the need for a proper framework within which the objectives of training can be addressed.

Jan 1, 1986

By R. C. Hopper, A. A. Mathews, T. A. Lang

DESCRIPTION OF PROJECT The Straight Creek Tunnel site is located approximately sixty (60) miles west of Denver, Colorado, on Interstate Route 70 in the vicinity of Loveland Pass, in the Rocky Mountains. The ultimate project will consist of dual two-lane vehicular tunnels with a building at each portal to house mechanical ventilation equipment and other installations. The tunnels run virtually east-west on an ascending 1.64 percent grade for a distance of approximately 8,900 feet, and will pass beneath the Continental Divide at an elevation of about 11,000 feet above sea level. The maximum cover is 1,450 feet and each tunnel is approximately 48 feet wide by 50 feet high as excavated. The work now under construction consists of the North Tunnel, which initially will have two-way traffic. Ultimately it will be the west bound lanes for Interstate 70. The completion of the North Tunnel will be the fulfillment of a long felt need for better communication through the high Rocky Mountains of central Colorado and is a vital link in Interstate Route 70. The early planning for a vehicular tunnel through the Continental Divide began in the late 1930's and between November, 1941 and May, 1943 an exploratory pioneer tunnel

Jan 1, 1997

By Shu DM, Moxon P

Subsidence profiles over longwalls at West Cliff Colliery (WCC) are predicted by three methods, NCB Emperical Method, Salustowicz's Profile Functions and Superposition of Two Critical Profiles. A method of deriving maximum subsidence using local data is also presented. For the first four longwalls, the results are compared with those from the subsidence surveys conducted during and after the extraction of each longwall. Longwall V has not yet been extracted, so the results are for the predicted subsidence profile. Superposition of two critical profiles is carried out in an attempt to check the principle of superposition. In addition, strata movement above the extracted longwalls is discussed.

Jan 1, 1986

By Norihiro Murayama

The hydrothermal syntheses of zeolites from coal fly ash were carried out using NaOH and KOH as an alkali source. The cation exchange capacity (CEC) and the ion exchange selectivity were investigated for the zeolites synthesized by a hydrothermal treatment. The effective usage of the zeolite as a cation exchanger was considered from the viewpoint of engineering. Zeolite P, HS (hydroxysodalite) and K-CHA (potassium-chabazite) are mainly formed as zeolite species in NaOH or KOH solution at 393K. The zeolite P and K-CHA have a large exchange capacity as a cation exchanger. The cation exchange isotherms of various monovalent and divalent cations with various zeolites are investigated. The order of selectivity of the zeolites is as follows, NH4+> K+> Li+.For the divalent cation, the largest removal amount is obtained for Pb2+ in the low equilibrium concentrations below 0.2mmol/dm3, and almost perfect removal can be achieved for Pd2+. The order of selectivity of zeolites in low concentration is expressed in the following order; Pb2+> Co2+> Cd2+> Ca2+> Mg2+> Ni2+. Ii is considered the zeolites obtained from coal fly ash can be used as an excellent cation exchanger.

Jan 1, 2006

By S Jahanshahi, T Norgate

In single stage copper making appreciable amounts of copper report to the slag phase. Various strategies are available to minimise copper losses to the slag. However a slag treatment stage is likely to be required in an economically viable process. A number of slag treatment process options are available and include: flotation, leaching and thermal reduction. In the design of an industrial process some type of economic as well as technical analysis of these options will be required. In this paper an outline of the techno-economic analysis procedure used to design a single stage copper making process is presented. The calculated operating and capital costs of industrial copper making processes are compared and used to determine the optimum single stage copper making flowsheet. The most economic slag treatment options is flotation of slags containing low amounts of copper.

Jan 1, 2000

By F. Julius Fohs

With portions of two coal basins within its borders and a few scattered fields already developed, the question arises: What is the future of Kentucky as an oil-producing State? Is the long list of failures due to lack of commercial pools, or unintelligent prospecting? A study of its beds and irregularities of structure points not only to a large waste of development money on unpromising areas, but also to the presence of a few structures well worthy of development. The surface rocks of Kentucky show in succession more than 4,000 ft. of Paleozoic sediments and more than 2,000 ft. of Cretaceous, Tertiary, and more recent deposits. Folding and erosion have brought these beds to the surface, where they have been observed and studied in detail by my associate, James H. Gardner, myself, and others. This has given opportunity to observe the beds offering suitable reservoirs and having the proper impermeable covering; also the mapping of outcrops and outcrop lines, taken in conjunction with available well records, indicates that certain areas are worth testing, and with even greater definiteness shows areas which should be excluded, as devoid of possibilities. West of the Tennessee River, Cretaceous, Tertiary, and Quaternary sediments occur so that all trace of ancient folding is obliterated, the sediments overlapping unconformably Mississippian rocks. This area embraces 2,000 square miles, or one-twentieth of the area of the State, the Paleozoic rocks covering the remainder. Since there is nothing upon which to base the location of tests for oil and gas in the Cretaceous-Tertiary beds of Kentucky, the Paleozoic area will be chiefly considered. The distribution of Paleozoic rocks in Kentucky is centered about the north-northeast striking Cincinnati geanticline, bringing to the surface on the Jessamine dome the oldest rocks exposed in the.State, those of the Devonian, Silurian, and Ordovician systems. On either flank of this great earth-arch are the Mississippian rocks, sloping gradually beneath the coal-measure basins to the west and to the east. West of the western coal basin, and. between it and the Cretaceous-Tertiary rocks further west, is a high area of Mississippian rocks. Crossing the State

Jan 1, 1915

By F. Milton Lewis, Roshan B. Bhappu, James L. Coburn

FOREWORD-To comminute is to pulverize, but, in mining technology, "comminution" includes all the multiple crushing and grinding operations on ore, rocks, coal, and certain other bulk materials. The primary objective of this two-part article series is to provide the reader with basic information and guidelines for designing comminution systems. Part One is confined to ore processing operations, where size reduction is required to liberate the valuable minerals so that they may be concentrated and recovered. Part Two will illustrate various design techniques through practical examples.

Jan 9, 1976

By Nural Kuyucak, Bohumil Volesky

"Extensive screening revealed a seaweed (alga) biomass type which in its non-living state possesses a very high cobalt sequestering capacity comparable to that of activated carbon and the ion-exchange resin currently used in the cobalt production process. Performance of the new bio-sorbent material was studied by examining its equilibrium metal uptake isotherms generated under different solution conditions such as initial cobalt concentration pH, temperature, and the presence of selected cations and anions. The rate of cobalt uptake was determined, which is a crucial parameter for recovery process design. Almost all cobalt sorbed can also be desorbed with a solution of CaCI2. The bio-sorbent material can be used repeatedly in the sorption-desorption cobalt concentration process. IntroductionIt has been well documented that certain types of microbial biomass, living or non-living, possess a high potential to sequester and accumulate inorganic ions present in aqueous solutions. Metal concentration by microbial biomass from a solution is termed bio-sorption. This phenomenon is quite complex and includes adsorption of metals onto the surface of a microorganism and/or into the cellular structure in combination with ion-exchange, complexation, and/or micro-precipitation. Bio-sorption is generally considered to be a rapid physical/chemical process. The cell wall structure is porous and allows metal ions, as well as large organic nutrient molecules, to pass freely through. Polysaccharides of the cell wall could provide binding amino, carboxyl, phosphate and sulphate groups. In addition to these functional binding groups, polysaccharides often have ion-exchange properties. Sometimes, bivalent cations, such as Ca2+ or Mg2+, help the formation of ionic bond bridges between the negatively charged cell surfaces and positively charged cations in the solution, Proteins in the cell wall could offer functional groups and also offer peptide bonds to bind ions. Interactions between metal and the cell wall components are responsible for the sequestering of metals by way of bio-sorption. Many metals feature a complex solution chemistry and it is not always possible to determine what ionic species are actually present in the solution. The equilibria involved are dependent on pH, concentration, the anions present and other factors. The transport system for the ions are sometimes dependent on both temperature and energy. Biosorbent material could also be regenerated for multiple reuse."

Jan 1, 1988

By R. T. Grant, C. Bazin, D. Hodouin

It is shown that most of the variation in the results of semi-batch flotation tests is related to the unavoidably stochastic nature of the flotation process. The preparation and analysis of flotation samples and, to some extent, operator error in performing the flotation test procedure are responsible for a small proportion of the observed variability of the calculated flotation performance indices

Jun 17, 1905