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By Ross W. Smith

Many studies have been made of the microflotation of quartz (1,2,3,4,5,6) and alumina (3,5,6, 7,8) using various anionic and cationic hetero- polar hydrocarbon surfactants as collectors. A few studies have been made on these minerals using amphoteric hydrocarbon collectors ( 9,10, 11,12) and only a few studies have been made on the use of fluorocarbon surfactants as flotation collectors (13,14). The present investigation compares microflotation response of the two minerals in hydocarbon and fluorocarbon collector systems of the anionic, cationic and amphoteric types. An attempt is made to relate flotation response of the minerals to their electrokinetic behavior and the pKa values of the collectors.

Jan 1, 1979

By Michael Kaplan

An investigation was conducted of the use of a mechanical rock splitter as the primary means for rock fragmentation in underground hard rock mining systems. Analyses and scale model tests showed that reasonably sized splitters that could be mounted on the booms of conventional drill jumbos were capable of fragmenting over a ton of rock per cycle. Detailed drill-split mining systems were developed for entry development, room and pillar, bench mining, and cut and fill mining. Economic analyses of these systems showed them to be generally competitive with conventional drill-blast methods. Except for bench mining, drill-split offered substantial cost savings over drill-blast. The investigation also included a technical evaluation of the mechanical splitter, an analysis of health and safety, and a determination of the potential applicability of drilling and splitting.

Jan 1, 1979

The Environmental Session will consist of five papers dealing with various aspects of trace elements associated with coal. Analytical procedures to determine the amounts of trace elements will be discussed. Other papers will deal with trace elements in streams downstream from coal mines, potential pollution from wastes from coal preparation plants, potential recovery of trace elements, and potential pollution from trace elements as a result of the combustion of coal.

Jan 1, 1979

By C. Hellar

A new dual-boom remotely controlled roof bolter was designed, fabricated, and then tested in an underground coal mine. Remote-control functions allowed complete bolting cycles to be performed on two booms with both operators located within protective cabs. Capabilities included 3-to 6-foot-long bolts in 5-to 8-foot seams, limited to bolts 20 inches shorter than seam height. Machine was in compliance with all regulations including dust collection, machine lighting, and permissibility.

Jan 1, 1979

By J. S. Fox

Major-element data for unaltered, unmineralized felsic host rocks from a number of stratigraphically simple, massive volcanogenic Zn-Cu(-Pb) sulphide deposits of low metamorphic grade have been compiled. The petrochemical affinities of these host rocks have been determined (by standard means and by discriminant analysis) and compared. This comparison indicates that volcanogenic deposits in felsic terrains are not restricted to the classical calc-alkaline rock association as previously thought, but can actually be hosted by rocks showing a range of iron content. There is a positive correlation between differentiation trend and are tenor. Zn-Cu ores usually have iron-rich felsic hosts (most Canadian Shield deposits); Pb-Zn -Cu ores have iron-poor felsic hosts (Japanese, Iberian and Tasmanian deposits). This parallels the antipathetic relationship between iron content and background lead levels evident in young, unmineralized, island arcs as well as in many older belts. Correlations between differentiation trend on one hand and massive ore mineralogy and the relative proportions of various rock type (including rhyolite, quartz-porphyry and coarse pyroclastic rocks) on the other are also evident. It is concluded that the recognition of a calc-alkaline differentiation trend cannot be used as a prospecting guide, as has previously been proposed. However, in view of the above correlations, the recognition of a given trend may aid in the formulation of an effective exploration philosophy.

Jan 1, 1979

By C. Jardine

The concept of the system is to minimize costly unscheduled breakdowns of equipment by replacing components earlier than their "life" expectancy. Periodic unit services are scheduled according to pre-set constraints. Service sheets are generated by matching a job and component master listing based on assigned cyclic component lives. The system can provide accountability of all man-hours reported and history information can be selectively retrieved. By reducing unscheduled equipment shutdowns, this system allows for better utilization of manpower and an overall improvement in equipment reliability and availability.

Jan 1, 1979

By Harry M. Parker

Exploration for sandstone-type uranium ore bodies which will be exploited using underground mining techniques is usually executed in sequential fashion. Geostatistical methods can be used at the earliest exploration stages to design drilling programs which have a high probability of success in the location and delineation of mineable ore-grade mineralization, should such mineralization exist. In succeeding development stages, geostatistics may be used to outline and define the potential grade of reserves and to apply confidence limits on the grade estimation. Delineation of mineable reserves for mine planning requires extensive development drilling; using such drilling data geostatistical methods may be used to minimize the drilling needed to achieve a desired level of confidence in the calculation of mineable uranium ore grade and tonnage. Because sandstone-type uranium deposits tend to be pod-shaped and are generally aligned along a mineralized trend, this paper proposes a geostatistical method of calculating uranium ore reserves which accounts for this fact and predicts the area within a trend which is underlain by ore. This method uses an indicator value; that is, drill holes which contain mineable ore-grade intercepts are coded as 1, those that do not are coded 0. The indicator may be kriged over the mineralized trend to obtain an estimate of the area underlain by ore. The thickness and grade-thickness may be kriged, and the average ore grade may then be obtained by dividing grade-thickness by thickness, as is conventional for stratabound deposits. The mean grade is then multiplied by the kriged mean thickness to obtain an estimate of the volume, and thence tonnage, of mineable ore within the trend.

Jan 1, 1979

By J. J. Lewis

In the mid-1970's a major new prospect was proved in a previously unworked region of North East Leicester- shire, United Kingdom. Preliminary estimates from borehole information showed over 500 million tonnes of recoverable reserves. A special Planning Team was set up, to co-ordinate the work for the two local Areas, South Nottinghamshire and South Midlands (management of production of the UK National Coal Board is organised in twelve such Areas). The team was led by one of the authors as Deputy Director, Mining, North East Leicestershire Prospect (NELP). The remit imposed by the National Coal Board was to analyse the possible options of number, location and eventual rates of output of shaft or drift access; to select a recommended alternative in the light of geological, mining, topographical and environmental considerations; and prepare submissions in accordance with standard Board practice on major projects - such submissions including detailed engineering design, financial appraisal, and full risk assessment. To assist the Planning Team, surface and underground consult- ant engineers were appointed to prepare feasibility studies of specific civil and engineering problems.

Jan 1, 1979

By R. D. Brown

This article summarizes some of the principal features of the taxation of industrial mineral mining in Canada. Where the rules applicable to such operations differ from those pertaining to the production and processing of precious and base meta s (non-industrial minerals), the two sets of rules are compared. If a conclusion could be drawn from such an over-all comparison, it may be that the total tax burden on an industrial mineral mine can be considerably more onerous than on both base meta mining operations and manufacturing profits.

Jan 1, 1979

By Berthold Pilz

The importance of a power economy that is efficient both in technological and economic terms has been clearly recognized in recent years. In 1977 the German Federal Government therefore introduced its Energy Research and Energy Technologies Program 1977-1980, which consolidates the government activities in the field of nuclear and non-nuclear energy research. The priority objectives of this program can be summarized as follows: safeguarding the medium- to long-term energy supply in the Federal Republic of Germany at reasonable overall macroeconomic cost, taking into account the requirements of environmental protection and the safety of the population. In the field of coal mining technologies, about 200 research projects are currently under way. A total of DM 1.7 billion is earmarked for research to be conducted in this area between 1977 and 1980.

Jan 1, 1979

Continuously monitor and record respirable dust levels underground by a reliable, sensitive, and fast-response device. Approach A light-scattering photometer, having a LED (Light Emitting Diode) light source and other significant improvements, has been designed and incorporated into a portable continuous monitor. How It Works The monitor continuously draws air into the sampling inlet through a cyclone that removes dust particles larger than respirable size. The dusty air enters the photometer vertically downward through a cylinder which is intersected by the optical system. (This cylinder appears as a circle in the drawing of the photometer.) The center of he column of dusty air intersects a beam of pulsing light from the LED, causing some of the light to be reflected, scattered, and refracted. Only the light that is scattered at an angle of about 700 from the light beam passes through a lens to the photodetector which generates an output voltage Signal proportional to the dust content in the air. This signal is detected, amplified, and converted to a digital readout directly in milligrams of dust per

Jan 1, 1979

By Gerald C. Dohm

INTRODUCTION After a mining company has discovered a mineral deposit, the problem is then how to mine and process that deposit the best way. The principal problem facing managers or engineers who must decide on mine plant size, equipment selection, and long-range scheduling is how one can optimize a property not only in terms of efficiency but also as to project duration. Mine opti¬mization is dependent upon the interaction of con¬tributing parameters which leads to maximizing the net present value (NPV) Realistic mine planning is the key, to the analysis. The process is to be used when evaluating undeveloped properties or when a complete revamping of existing facilities is scheduled The proc¬ess is not intended for detailed mine design but rather for property evaluation and feasibility studies. The derivation of the various input parameters will only be discussed to the point where a meaningful correlation can be made with the overall analysis. The interrelationship of the parameters will be the central point because most company guidelines and financial analysts have their own standards when deriving the various inputs. Assume that the data is totally acceptable and pro¬vides at least the following categories of information and guidelines- (1) mineral and waste inventory; (2) geologic, hydrologic, and geotechnical criteria; (3) topographic layout including property boundaries; (4) metallurgical flowsheet, recovery and design criteria; (5) access, water, power, and environmental base-line study; and (6) financial constraints (minimum rate of return, payback period, etc).

Jan 1, 1979

By Floyd JM

Pilot plant trials showed the effective ness of the submerged lance SIROSMELT technology for altering the composition of iron blast furnace slags as a preliminary step to produc- tion of formed materials. Mixtures of oil and air were injected into a bath of liquid slag to provide the heat required for melting the additives and to provide very turbulent conditions which resulted in complete dissol- ution of added fluorspar within one minute and almost complete dissolution of silica in two minutes. Sulphur lost during injection was readily made up by addition of pyrite or pyrrhotite. A stable foam could be readily made and broken down and the foamed slag appeared suitable for extrusion or forming into shapes.

Jan 1, 1979

By J. C. Weimer

The goal of Bethlehem's mining research program is to improve both the safety and productivity of our mines through the use of new equipment, new technology and new mining methods. Although we can all agree on the value of such goals, achieving them can be a costly, time-consuming and sometimes frustrating experience. However, the potential benefits of lower costs per ton and better safety in an increasingly more stringent and confusing regulatory environment make the expended effort worthwhile. At Bethlehem we feel that the mining companies are in the best position to determine the needs of the industry, and coal companies have the incentive as well as mine sites at their disposal for testing. Therefore, the mining industry should be leading the research effort

Jan 1, 1979

By R. R. Young

Prior to 1903, the world's supply of sulphur was primarily from surface deposits in Sicily. The discovery of the first salt dome sulphur deposit in 1867 and successful development of the Frasch process for recovering the sulphur resulted in a large part of this essential element being supplied from these mines since 1920. Although the basic process is the same today, engineering and technological developments have evolved to allow its application under many adverse conditions. These and other challenges for the industry in today's environment will be discussed in the paper.

Jan 1, 1979

By Donald P. Richards

Is a shaft the same as a tunnel and can it be approached in the same manner for design and construction? The most obvious difference between a shaft and a tunnel is that of orientation; whereas a tunnel is commonly near horizontal or slightly dipping, a shaft is commonly vertical or steeply inclined. As a result, design and construction methods employed for tunneling, in general, cannot be directly applied to shafts, although some of the basic concepts of behavior are quite similar. Many of the shafts that have been sunk in various parts of the world are owned by private mining companies. Each company has generally accumulated years of experience in shaft sinking and mining techniques pertinent to its particular geographic location. When a new shaft is to be sunk or an existing shaft deepened, the tendency often seems to be to continue to use the methods that have been used successfully in the past.

Jan 1, 1979

By W. E. Bardelmeier

The high speed conveyor type self unloading bulk carrier concept has been around for about 70 years. Although the design was developed, refined and steadily improved in the Great Lakes, to date limited numbers of such vessels have emerged in the bulk ocean trades, and these have tended to concentrate within specific mineral trades. For example, North American gypsum companies have embraced conveyor self unloaders to the point where such vessels almost exclusively carry the gypsum requirements of this part of the world. One major aluminum company has developed an impressive fleet capability in self unloaders. Application of other ships tends to be fragmented through several mineral trades. A few years ago a new phenomonen began to appear on the Great Lakes. Whereas it had historically been accepted in that region that self unloaders were effective vessels for the minor bulk trades including limestone, coal, salt, gravel and sand; they had seldom been employed heavily in the big volume iron ore trades. Suddenly, however, the new generation of 60,000 ton Lakers which emerged were all designed as high speed self unloaders. The new vessels intended to trade especially in ore, or alternatively especially in coal, have somewhat different internal features, but the important point is that all are self unloaders.

Jan 1, 1979

By Konrad J. Banaszak

At least for the time being, these seems to be general but not universal agreement that Mississippi Valley type ore deposits formed entirely or in major proportion from heated connate brines (e.g. 1) Even with that agreement, major questions remain. I will present a coherent geochemical model and look at alternative views in the context of that model. The pattern of the following discussion is 1) the general geochemistry of the ore fluid, 2) the density-temperature relations and possible mechanisms of flow of those fluids, 3) the mechanisms of transportation and deposition of the ore minerals, and 4) a summary of a coherent model of genesis. The data equivocally define much about the deposits. The answer is still elusive.

Jan 1, 1979

By F. L. Wilke

Underground mining is a very complicated and complex industrial activity. The uncertain and, in most cases, the incomplete knowledge of the geological and mineralogical nature of the deposits can cause unforeseen difficulties. For a safe and uninterrupted operation, in addition to good planning and scheduling, reliable and up-to-date monitoring and control of all processes and conditions become necessary. Today, this is even more important in view of increasingly difficult working conditions, poorer grades, and more complex and expensive machinery. In short, large capital investment and higher risk of financial losses are involved in modern-day mining operations. Monitoring and control of the underground mining process has become a very complex and difficult task in itself. Many different systems are available, and the correct choice .is of utmost importance from both the economic and safety points of view. This chapter will deal with aspects of underground production monitoring and control. There are, however, many other areas of equal importance which are covered in an excellent manner in a hand- book by Olaf (1976) on monitoring and control of underground operations.

Jan 1, 1979

Tyre costs constitute 20-40 per cent of the operating cost of large haulage trucks, and tyre pressure maintenance is an important factor in minimizing costs.In the past, control over the hot (built-up) pressures of earthmover tyres has been inaccurate and inconsistent because it has not been possible, in a practical way, to measure the tyre's contained air temperature.A method for measuring this contained air temperature has now been devised using a bi-metallic probe thermometer inserted through the valve stem. Using these measurements in conjunction with a pressuretemperaturechart drawn up using the general gas equation, very accurate control over hot tyre pressures is now possible.

Jan 1, 1979