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By E. H. Bentzen

The purpose of this paper is to explain the production of sand for glass manufacturing and the reasoning behind the sand specifications set by the glass industry. In order to discuss the production of glass sand, there is a need to understand what glass is and how it is made. Therefore this paper discusses glass, as well as sand beneficiation.

Jan 1, 1977

This chapter summarizes data on crude mineral production for the United States, its island possessions, and the Commonwealth of Puerto Rico. Included also are tables that show the principal mineral commodities exported from and imported into the United States, and that compare world and U.S. mineral production. The detailed data from which these tables were derived are contained in the individual commodity chapters of volume I and in the State chapters of volume II of this edition of the Minerals Yearbook. Although crude mineral production may be measured at 'any of several stages of extraction and processing, the stage of measurement used In this chapter is what is normally termed "mine output." It usually refers to minerals or ores in the form in which they are first extracted from the ground, but customarily includes the product of auxiliary processing at or near the mines.

Jan 1, 1977

By W. G. Cornwell, R. J. Hisshion

The development of a process for the treatment of telluride concentrates at Emperor Gold Mining Co. Vatukoula, is discussed. The concentrate is produced by flotation in cyanide solution immediately after milling. Two stages of cleaning are employed and a high-grade concentrate is produced usually containing more than 50% of the precious metal. The process developed in the first instance involved batch roasting followed by batch leaching in strong cyanide solution, recovering gold and silver only. The procedure currently employed is chemical oxidation of the tellurides using hypochlorite as the oxidant in a basic solution of a caustic soda and sodium carbonate. After oxidation the gold and silver are recovered by cyanidation. The residue is then leached with sodium sulfide and elemental tellurium precipitated with sodium sulfite.

Jan 1, 1977

The Tailings Leach Plant at Chingola employs a Leach/Solvent Extraction/Electro- winning process and contains the largest solvent extraction plant in the world, with design liquor flow rates of 55 m3/min. A pilot plant constructed to provide design data also indi- cated areas of uncertain operating and control performance and led to a decision to model the whole circuit to determine the overall dynamic behaviour and basic operating characteristics. Details of the plant flowsheet are given and the basic physical and chemical' equations required for the simulation defined. Each unit operation is considered separately and details of the mathematical models used for their simulation presented.

Jan 1, 1977

By David Pentz, Paul Hodges

GENERAL INTRODUCTION The object of this paper is to discuss those aspects of open pit mine design which are affected by geotechnical factors. The temptation exists for some practitioners of geotechnical engineering to believe that this relatively new engineering discipline is the ‘be all and end all of mining.’ In the opinion of the authors, this is fallacious but, as our ability to put numbers to the behaviour of rocks and soils improves, it is clear that geotechnical engineering will become an integral and important part of designing and operationg mines success- fully. Open pit mines in the context of this paper also includes open cast mines, where the 'ore" is extracted and the waste material is immediately replaced or ' backfilled in the mined portion of the pit. Open pit mines operating today move from very small tonnages a day to in excess of 400,000 tons per day. Several mines are operating and are being designed to capital expenditure for such projects in some cases exceeds five hundred million dollars and in a few cases will exceed one billion dollars. The size of this investment means that financing will have to be provided from banks or joint partnerships. This financial environment means that planning will be carefully scrutinized by experienced representatives of financial institutions or other mining companies. All too often a project has been put in jeopardy because the personal desire of one or two men to make a project proceed has caused incomplete planning or perhaps in some instances deliberately leading observers 'down the garden path.’ In our opinion the day is rapidly arriving when the quality, logic, practicability and completeness of the planning will make the difference between securing financing or not and, in the cases of existing open pit mines, of the difference between survival and closure.

Jan 1, 1977

By Malcolm C. Bridges, Ian A. Goddard

INTRODUCTION Mount Isa mine is a major producer of both copper and lead-zinc- silver ores. During the 1975/76 year, 4.3 million tonnes of copper ore were extracted at an average grade of 3.4%, and 2.4 million tonnes of lead-zinc-silver ore at average grades of 7.0%, 6.7% and 173 grams per tonnes respectively. Systematic lead-zinc mining has continued for just over 45 years and copper mining for just over 30 years. Virtually all mining is underground. The composite and somewhat schematic longitudinal section of Figure 1 shows the overall distribution of ore at the Mount Isa mine. The mine can be roughly divided into two parts about a central shaft complex: to the north there is predominantly lead-zinc ore and to the south there is copper ore. Underground operations are serviced by three shafts in the central shaft complex (P61, R62 andU62) and another to the south in the copper mining area (X41). Mining is spread over a total strike length of 2.9 km and extends to a depth of 960 m. Currently, lead-zinc ore is being extracted between 15 and 11 levels and is hauled to the central ore-hoisting shaft on 13 and 15 levels. Copper ore is being extracted between19 and 13 levels and is hauled to the central shafts on 19 level. The principal lead-zinc mining methods used now, as they have been over the last ten years, are sublevel open stoping and cut-and- fill stoping, with about equal tonnages of ore from each (Figure 2). Since about 1970, there have been several interesting developments in lead-zinc mining methods and procedures, principally: • the development of an effective method for the recovery of pillars between open stopes and • the evolution of safer and more productive cut-and- fill methods. During this period also, the focus of mining has moved 120 m deeper

Jan 1, 1977

The last two years have seen a rapid change-over from mechanised cut and fill. stoping to the more economic and productive long hole open stoping method, such that today more than 80 per cent of total production is won from open stopes. At first drilling was by sub-level rings and/or parallel up and down holes from inter- mediate sill horizons using conventional exten- sion rod equipment. Sub-levels were developed no more than 40 metres apart to allow accurate drilling. Compact, crawler mounted in-the-hole hammer equipment was introduced as soon as it became available in Australia. Today, all open stope drilling is done with three Atlas Copco ROC306 rigs and two Ingersoll-Rand CMM jumbos. Fans of 115 mm diameter holes, varying from near vertical down holes to horizontal, are drilled with a burden of 3 m. Toe spacing varies from 3.5 m to 4 m. An Atlas Copco DG418 booster compressor is used to boost run-of-mine air from 700 kPa to 1400 kPa in the areas of longest drilling. This has improved overall drilling performance in these areas by 40 percent.

Jan 1, 1977

By Brown A

An experimental evaluation of a selective agglomeration process in which an agglomerated coal rich phase was produced as a result of mixing light oil to various raw coal slurries is described. The beneficiation achieved by this method is compared to that obtained bv conventional froth flotation. The results suggest' that oil agglomeration is a more selective process than froth flotation and is less sensitive to variations in feed pulp density. Selective agglomeration has the additional advantage of producing a low moisture content product. The effect of replacing flotation filter cake with an equivalent amount of selectively agglomerated product in coke-making was studied with the aid of a pilot-scale coke oven. The results suggest that the principal effect of such a measure is to increase the bulk density of the charge.

Jan 1, 1977

By Weller K. R, Trahar W. J

The Mount Lyell Company treats some 2.3 million tonnes of ore annually, mined from a number of orebodies on the field. Blended ore is essentially a quartz-sericite schist containing about eight per cent of pyrite and three per cent of chalcopyrite. Four-stage crushing and two-stage ball milling are followe by selective flotation for copper. Pyrite is recovered from the coarse fraction of dopper circuit tailings. A detailed survey involving examination. of 82 samples provided information on the size- by-size behaviour of the principal ore constituents throughout the grinding, copper flotation and pyrite flotation sections of the circuit. Results for the copper and pyrite flotation sections are presented in the paper, and it is shown that over half the copper reporting to the final tailing (5% of copper in the feed) is plus 100 microns and that the major pyrite loss is in the desliming cyclone overflow. These data proVide a basis for assessing potential methods of circuit optimisation.

Jan 1, 1977

By Malcolm J. McPherson

INTRODUCTION The use of computers to assist the mine ventilation engineer began to grow in the early 1950s when electrical analogue devices were developed for the analysis of mine airflow systems in Europe and the United States (l,2,3). The need for quantitative planning of airflows in mines had become pressing and analogue computers fulfilled a useful purpose for over a decade. From about 1964 onwards, digital computer programs for mine ventilation network analysis became available (4,5) and, superseding the analogues, spread rapidly throughout the major mining countries. The successful implementations of such programs resulted in further research being directed towards the development of simulation programs to model the quality as well as the quantity of air flowing through underground workings. It is no understatement that digital computers have revolutionised environmental planning techniques in modern mining industries. This paper discusses the complex interaction of natural and mining factors which governs environmental hazards in underground mines and further indicates some of the simulation techniques which have entered practical usage or are at an advanced stage of development. THE PROBLEM OF ANALYSING THE MINE ENVIRONMENT The traditional methods of approaching environmental problems underground were based largely on empirical or intuitive techniques. The reason for this lay in the intricate relationships which exist between the many variables that influence the mine environment - and which limit the use of purely analytical methods to the simplest of cases. In order to illustrate the need for simulation techniques, Table 1 shows the three most widespread mine environmental hazards

Jan 1, 1977

By John Dasher

Extrapolation is a useful technique, but it can be overdone. Seldom is it justified to study over a range of 1 to 6 and extrapolate the results to 150,000. It is especially dangerous if the extrapolation is based on a false assumption. The authors assume settlers scale-up by residence time rather than by area, admit their result (a settler depth of 7 m) is "unreasonable" and suggest longer, wider, shallower settlers might be better. Various authors have noted for a copper-LIX system a total flow basis of 2 gpm per sq ft for sizing settlers. The results of this are compared with those in the paper in [Table 7]. The authors note that flooding of their settlers was never approached. Thus the smallest unit calculated is understandably twice too big. The largest however, is 5% of the required size. I note that the figures in [Table 6] for 1/min/cm2 are based on plan area rather than cross section as titled and are wrong by l0 4. A flow of 2050 1/min/cm2 is about Mach I. It is also 10 5/3 or 46.5 times that of the little one, although the abstract says the design was based on constant flow rate per unit cross section.

Jan 1, 1977

By J. Sajkiewicz

In a synthetic way discussed are certain results of papers realized at the Wroclaw Technical University in a field of the theory of exploitation of machine systems with conveyor-belt transport. The attention is paid to the two lines in these works which are concerned with the development of analytical as well as simulation methods, in both cases realized with the help of digilat computers.

Jan 1, 1977

By M. G. Taverner

Research was conducted into cold briquetting dross arisings and metallurgical coke fines from an Imperial Smelting Furnace (I.S.F.) as an economic means of agglomerating fine materials for smelting in a blast furnace. A mechanism was postulated whereby strong bonds were developed within the briquettes; laboratory scale smelting trials and full scale plant trials are included in the paper with a description of a two tonne/hour briquetting pilot plant. Benefits from smelting briquettes in an I.S.F. were measured directly in metallurgical coke savings and, indirectly, by a significant improvement in sinter plant productivity.

Jan 1, 1977

By Snowdowne J. B H

Rand Mines, Limited, located in Johannesburg, Republic of South Africa has recently completed feasibility studies which have lead to the initiation of two major coal strip mining ventures. A minicomputer based mine planning system was developed to perform the feasibility studies. The broad approach of this system is to utilise inter.-actively the specialist skills and interpretative abilities of mining engineers and geologists. This paper reports briefly on the outline of the system and at greater length upon certain aspects of its use.

Jan 1, 1977

By J. S. Fox

"Pyroclastic rocks are useful guides to volcanic centers due to the tendency of their fragments to increase in size and volume toward the source vent. The felsic rocks of these centers can be the prime hosts of base metal deposits in the Precambrian Shield; their sub-volcanic equivalents are often the focus of porphyry copper mineralization in the Cordillera. Quantitative mapping of pyroclastic rocks has not yet developed into a routine prospecting tool in Canada, however, possibly due to the cumbersome nature of existing manual techniques and their limitation to structurally simple terrains.A rapid pyroclastic mapping method has been developed whereby the field geologist acquires only a down-plunge outcrop photograph, a record of the fragmental deformation ellipsoid and a record of some descriptive features from each station. Mean fragment size and volume percent are obtained later in the laboratory from a photo-enlargement: by means of a digital analyzer. A computer program uses the strain parameters to 'undeform' the field measurements and obtains genetic information from the descriptive data. Results can be superimposed on a geologic map, with values for each station being represented by a dot of a specified diameter corresponding to the size or volume percentile range to which the value belongs.Control traverses were run over the pyroclastic rocks surrounding the Anderson Lake mine and the Flin Flon South main shaft in northern Manitoba. In both locations, the mapping has delineated regular increasing trends in mean size and volume per cent toward the head frame."

Jan 1, 1977

By J. S. Young

During 1975, the Reclasource Corporation constructed and commissioned a plant for the recovery of mill scale, coke breeze, blast furnace dust, blast furnace sludge and basic oxygen furnace dust at the site of Crucible Alloy Division, Midland, Pennsylvania. The Reclaform Process was employed as the criteria for plant design. This Process takes the solid in-plant fines as listed above, commonly found in integrated steel mills, sizes and forms them through the use of a carbonaceous binder briquetting system and cures the binder through a final heat-treating step. 15,000 tons of Reclaform briquets have been tested in the Crucible blast furnace in several campaigns structured to assess material handling properties, burden feasibility and finally culminating in an iron and carbon assessment campaign. Data are presented from the records of the blast furnace operation and conclusions are drawn that both iron and carbon utilization have been demonstrated.

Jan 1, 1977

By David Runnels

In September 1970, the Quebec Cartier Mining Company, started development of the Mount; Fright iron ore mine. The estimated ore reserve is in excess of 1,000,000,000 long tons with an average grade of 31.5% Fe. The run of mine ore is crushed, ground and concentrated to a product having 66% Fe and 5% silica at an annual concentrate production rate of 18.4 million long tons. The daily production rate of over 50,000 long tons of concentrate necessitates a daily mine output of approximately 250,000 long tons of material of which 50% is waste. The mine is located in the Province of Quebec, close to the Labrador border approximately 600 miles north-east of Montreal. The development of the mine necessitated the construction of an all electric one thousand housing unit townsite along with associated services such as a shopping center, swimming pool, arena, school, etc... A one-hundred mile long, 315 K.V. Dower line was built between the mine site and the Hydro-Quebec 735 K.V. existing power line between Churchill Falls and the Montreal area. The construction near the mine of a beneficiation plant was necessary to upgrade the 31.5% iron ore to a marketable product of 66% iron.

Jan 1, 1977

By S. S. Burns

"AbstractShovels of 18 cubic yard capacity and larger are described which incorporate advanced technology and techniques providing performance and operation tailored to meet the needs of open-pit mining.To achieve the goal s of increased production at lower cost with consideration of maximum availability, lower energy consumption per ton and low •impact on pit power, Harnischfeger Corporation developed a solid -state drive system (""Electrotorque"" - P&H trademark) and applied unique transmission methods.To date, more than 250,000 hours of experience in different parts of the world under varying operating and environmental conditions has proven that the ""Electrotorque"" shovel is the shovel of the future, today.This paper will discuss the electrical features and touch briefly on some mechanical features.Introduction to ""Electrotorque""THE hoist, crowd, propel and swing machinery of an electric mining shovel are driven by direct-current motors.A D.C. motor is used instead of an A.C. motor because the torque output per ampere input is at a maximum and the fact that it is doubly-fed (armature and field ) provides optimum flexibility in control.The power that is available in the pit is alternating current power. It is therefore necessary to change or convert this A.C. power to D.C. power so that the D.C. motors can be used."

Jan 1, 1977

By E. B. Graves

I have been asked to talk to you this morning about phosphate marketing and distribution. In discussing this I will attempt to answer such questions as: What is phosphate? Where do we get it? What form is it and how do we sell it? How do we distribute it? How is it applied? And last, but not least, What about the future? To start with, phosphate is one of the three primary plant nutrients. It is the element essential for root structure of plants. Plants, like humans, need a balanced diet. Thus, the amount of phosphate required by individual plants is, in part, related to how much of the other nutrients are used. Virtually all soils contain a certain amount of available phosphates. Back at the turn of the century the most common source of additional plant nutrient, including phosphates, was from cattle manure. The use of chemical fertilizers is something that has grown significantly during the last half century, and in particular, the last 20 years.

Jan 1, 1977

By David G. Chedgy

The Meadow River No. 1 preparation plant, owned by Sewell Coal Co. which is a subsidiary of the Pittston Co., was commissioned in the spring of 1974. A survey of the environmental noise levels was conducted, and the dominant noise sources identified. An engineering program was initiated to reduce the prevailing levels to a point that the operator's exposure would be within compliance with the MESA regulation for ear protection. The program was continued until compliance was achieved and the attenuation factors for each abatement device recorded. The highlights of this program will be presented with a discussion of the practicality of the devices utilized.

Jan 1, 1977