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By A. B. Rossetti

"THE MISSION TO Offshore Scotland was in my opinion a very worthwhile venture, as it indicated the scope of the offshore oil and gas business and how we might exploit it to the fullest here in Nova Scotia - if our offshore fields eventually become producing fields. The writer was able to attend a considerable number of lectures and as a result gained some valuable know-how on the engineering design, financing and operation of the North Sea oil industry. There are many new fields of technology that had to be developed to overcome the North Sea's hostile environment and a great deal of the same technology will have to be developed to win oil and gas from our continental shelf. The visit left me with several impressions, which in the main are:(1) The high order of investment required to develop offshore oil. The investment ranges from 10 to 20 times that required for a similar output on land. Each barrel of oil costs on the average of about $2,- 500 per barrel per day.(2) Because of the high investments required, before the first oil is produced the field must be brought into production at the earliest possible date and initial lead time from decision to production is less than four years. In the British Petroleum field, working at a depth of 450 feet will require an investment of $900,000,000 to develop a production of 400,000 bbl per day. (3) The size and complexity of equipment required is beyond anything ever imagined. Problems which must be overcome are such factors as water depth, wind velocities, wave height, wave period, long periods of darkness, low temperatures, distance from land, and fog."

Jan 1, 1973

By Otis M. Clarke

The Eufaula bauxite-kaolin district in southeastern Alabama is an important source of raw material for the refractory industries in the United States. At the present time, five companies are mining and processing bauxite and kaolin from this district and a sixth company is holding substantial reserves. Mining operations are expanding, but finding new ore reserves is a major problem. The Geological Survey of Alabama sponsored geologic research in the Eufaula district to: (1) investigate the

Jan 1, 1973

By Edward C. Mabbs

U.S. industry must increase its productivity or lose its competitive position in the rapidly expanding and inter-dependent world markets. Recent improvements in material handling techniques and equipment, coordinated with production processes, provide one of the greatest opportunities to increase productivity. Successful managers must learn how to take advantage of these material handling opportunities to gain competitive position.

Jan 1, 1973

By Kurzeme M, Willoughby D. R

Current research at the CSIRO, Division of Applied Geomechanics, into the mode of response of fill as a structural component has been based on model tests for prediction of behaviour and field observation of critical parameters. The procedure is summarised in four stages: (a) define the specific fill function (b) postulate the mode of failure (c) use models to quantify the conditions (d) monitor critical parameters to check or update the analysis in (c). The above procedure is used to postulate the failure modes of each of the possible func- tions performed by fill materials. Analytical techniques, or lines of investigation, are described for each of these modes and specific reference is made, where, possible, to an exis- ting mine environment.

Jan 1, 1973

Three -dimensional boundary value problems are difficult to solve. Indeed, while the separation of the scalar wave equation can be effected in 11 different coordinate systems, an analytic solution requires that the boundaries, both external and internal, possess the same symmetry as the coordinate system. Numerical methods are thus of great importance for the solution of such problems; however, despite the availability of high-speed, large memory digital computers , the solution to a significant three -dimensional problem is by no means trivial. It is unfortunate that the results reported here by Jones are invalid. Jones discusses a model in which a three-dimensional island lies off a linear coastline where all the interfaces lie in the coordinate planes in a Cartesian system. A downward plane em wave polarized with the electric field parallel to the linear coastline, and two of the islands coast, is incident downward. This, of course, requires that the incident electric field is perpendicular to the other faces of the idealized Cartesian island. The significant equation used by Jones for his finite difference calculations is [ ] where n2 = sµ? . is the conductivity, µ=µo is the permeability of the appropriate medium, and w is the angular frequency of a Fourier component of the incident field. We see that the displacement current term is omitted, which is an excellent approximation for the parameters of interest in this model. In the similar equation for the y- component of the diffusion equation, the same considerations which we are about to discuss are equally valid. It can be seen from the equation that the field components are related and thus any errors introduced will be propagated into all three components. The difficulty arises when Ex or E is perpendicular Y to one or other of the surfaces of discontinuity in s. The continuity of current at the air-earth interface (upper surface), e. g., jy, requires

Jan 1, 1973

By H. L. Ames, P. H. Jennings, R. W. Stanley

A process has been developed for leaching copper, lead and calcium from molybdenite concentrate. The leachant is a solution containing an oxidizing chloride (e. g., CuC12, FeC13) and an alkaline earth metal chloride (e. g., CaC12). Cupric chloride and ferric chloride, in the presence of 20-30% calcium chloride, are effective oxidants for chalcopyrite and galena. Calcium chloride, in addition to promoting the rate of leaching, serves to lower the solution pH and raise the boiling point. Leaching for two hours at 110'~ with a 1 % CuC12-10% FeC13- 30% CaC12 solution results in the extraction of up to 98% of the copper in molybdenite, 98% of the lead, and 79% of the calcium. Less than 0. 5% of the molybdenum is dissolved. The leach solution can be rapidly and effectively regenerated with gaseous chlorine and recycled. Build-up of copper and lead in the leach solution is controlled by discarding about 30% of the leach solution each cycle.

Jan 1, 1973

By R. E. Lindstrom

Electrooxidation techniques were investigated on a bench scale by the Bureau of Mines to determine the applicability of the process for extracting molybdenum and rhenium from low-grade molybdenite concentrates. Parameters affecting the extraction, such as pulp density, power consumption, reagent requirements for pH control, and electrolytic cell configuration, were studied. Molybdenum and rhenium extractions of 98 to 99 percent were achieved from several concentrates containing 4.76 to 28.6 percent molybdenum and 180 ppm to 1,000 ppm rhenium. Optimum results were obtained by maintaining pH values between 5.5 and 7.0 during electrolysis and allowing the final pH to rise to about 8.2. Reagent consumption was 4 to 6 pounds of sodium carbonate per pound of molybdenum extracted. The power consumption declined from a range of 12 to 25 kilowatt hours per pound of molybdenum extracted with immersion electrodes to 9.7 kilowatt hours with a bipolar flow-through cell; however, molybdenum extraction was independent of cell configuration.

Jan 1, 1973

By Jack E. Tress

The Bureau of Mines has been involved for several years in the development of processes for the recycling of solid wastes. As part of this program, a project was initiated to determine the feasibility of producing secondary pig iron from auto scrap. During the test period, 86,000 pounds of shredded auto scrap, along with petroleum coke and fluxing agents, was charged to a submerged-arc furnace of 1-ton nominal capacity. Eighty-eight thousand pounds of pig iron, with an average carbon content of 3.90 percent and an average copper content of 0.2 percent, was produced at an electrical consumption of 512 kW-hr per net ton. A cost estimate of the process showed that the pig, iron might be produced at a cost of $57 per ton.

Jan 1, 1973

This report, the second in an annual series, summarizes information on latest technological developments and advances, and identifies trends in mining and metallurgy based on a review of activities in the minerals industry in 1971. Exploration and mining data obtained from an annual canvass are presented for 1971 and are compared with similar data obtained over the past decade.

Jan 1, 1973

By Paul L. Russell, R. G. K. Morrison

9.1-CLASSIFICATION OF MINERAL DEPOSITS AND ROCK MATERIALS After a mineral deposit has been discovered, delineated and evaluated, the next step is to select a mining method that is physically, economically and environ- mentally adaptable to recovering the mineral from the deposit. The term "mineral deposit" is used to denote a concentration of mineral (including rock and coal). Even where there is considerable past experience available, many of the critical design criteria must be determined utilizing only information obtained from an examination of exploratory drill core specimens. The factors that affect this selection are as follows: (1) the spatial characteristics of the deposit (size, shape, attitude and depth); (2) the physical (or mechanical) properties of the mineral deposit and surrounding rock; (3) ground water and hydraulic conditions; (4) economic factors, including grade of the ore. comparative mining costs and desired production rates; and (5) environmental factors, such as the preservation of the surface overlying the mine, and the prevention of air and water pollutants. Of these factors, the spatial characteristics of the deposit and the physical (or mechanical) properties of the mineral and surrounding rock limit the methods that can be employed to mine it. Six types of mineral deposits are recognized, as follows: 1. Massive-A deposit of considerable lateral and vertical extent in which mineralization (or ore) is relatively uniformly distributed. Disseminated copper ores are typical deposits. Dome salt also is included in this classification. 2. Bedded or Tabular-A mineral deposit that parallels the stratification, most often in sedimentary rock, usually laterally extensive, and of limited thickness. Most coal measures and some evaporite mineral deposits (e.g., potash) fall in this class. 3. Narrow Vein-A zone or belt of mineralization (ore) typically long, narrow (less than 10 ft), often dipping steeply, and usually lying within boundaries separating it from neigh- boring rock. Many gold and other metallic minerals occur in narrow veins. 4. Wide Vein-As defined under narrow vein except that the vein thickness is greater than 10 ft. 5. Lentictclar or Pocket-An isolated ore body, or an enrichment of limited vertical and horizontal extent in a massive, bedded or vein deposit. Lead, zinc and iron ores often occur in this type of deposit. 6. Placer-A surface or near-surface deposit, usually tabular and may be of consider- able areal extent, containing mineral particles (e.g., gold, platinum) in detritus (e.g., sand, gravel). The rock materials associated with mineral deposits are classified as follows: 1. Detritus-Sediments and other accumulations of solid particles produced by the mechanical and/or chemical disintegration of rocks, and usually having a low cohesive strength and very low compressive strength (e.g.. soil, sand, gravel, alluvium, playa). 2. Jointed and Fractured-Unbonded-A rock mass, often occurring on or near the surface or in fault zones, in which the joints or fractures contain alteration or decomposition

Jan 1, 1973

By A. Visnapuu

High-grade synthetic rutile has been produced in the laboratory from domestic ilmenite concentrates by a new carbonyl process. The ilmenite was first reduced to convert the iron oxides to metal and then treated at temper-atures over 1000 C in high-pressure carbon monoxide (CO) to convert the iron to the pentacarbonyl. Rapid carbonylation was achieved in the presence of small quantities of selected promoters. Maximum iron removal occurred at temperatures between 110° and 130° C at CO pressures from 1,000 to 1,400 psig. Iron pentacarbonyl appeared as liquid and vapor in the reactor and could be removed by gravity flow and vapor transport. More than 90 pct of the iron was extracted in 2-hr experiments at pressures of 1,000 psig and above. The Ti02 product is porous owing to the removal of the iron, has the rutile crystal structure, and is suitable for chlorination. Waste disposal problems associated with the process would be minimal because the iron pentacarbonyl can be decomposed to produce iron powder or pellets for sale and CO for recycling.

Jan 1, 1973

By David A. Monaghan, Kenneth R. Maser, Adi R. Gurdar, D. Randolph Berry

7. Development of Acoustic Seal Checking System The acoustic approach was shown in Section 4 of this report to be the most promising concept for checking the seals. This section describes the development of this concept into a working hardware system to be used later in the field test program. This development effort included: (1) Theoretical analysis of the acoustic behavior in the mine using acoustic modeling- techniques. (2) Experimental determination of acoustic patterns in mine passages. (3) Refinement of the theoretical model. (4) Verification of final theoretical predictions in the quarter-scale laboratory model of a mine passage and seal. (5) Development of system specifications. (6) Development of the Acoustic Prototype Seal Checking System. 7. 1 Analysis of the Acoustic Seal Checker Concept The acoustic seal checker concept is based on a model which combines corridor acoustics and hole transmission theory. The idealized model for the mine sealing application is shown schematically in Figure 66. A high intensity acoustic- source is located in a corridor at a, position adjacent to the location to be sealed. The acoustic signal transmitted through the seal is monitored by a microphone pick-up placed on the opposite side.

Jan 1, 1973

By Richardson F. A

Techniques for flotation optimisation were investigated at Cobar [lines Pty:Ltd., in anticipation of the proposed installation of a computer and on-stream analysis. Successful laboratory and pilot plant tests for flotation performance optimisation using the Simplex Evolutionary Operation Technique (Simplex) lead to a full scale plant test using this method. The index developed for" Simplex response evaluation of flotation performance was based on metallurgical and economic criteria. This index was further modified to minimise the effect of head grade fluctuations. The test program was carried out on one of two parallel copper flotation circuits to allow comparison with normal "manual" operating control, and was conducted for thirty eight shifts. Results from the test section operating under Simplex direction were superior to those obtained using normal "manual" operating techniques and demonstrated the use of the Simplex Evolutionary Operation Technique as a method of reducing reagent consumption in flotation but, at the same time, maintaining satisfactory metallurgical performance. Experience in the use of the technique indicated the need for modifications to the rules of Simplex operations. Modifications were proposed, tested and appeared satisfactory.

Jan 1, 1973

By E. G. Williams

Underclays and shales are two natural resources associated with the coal measures. Underclays are widely used as the raw material for refractory, semi-refractory, and face bricks. Shales are useful for sewer pipe and lightweight aggregate. This study concentrates on the geologic controls over the properties of shales for use in the manufacture of lightweight aggregate, and the geologic controls over the properties of underclays for use in the manufacture of bloating ladle refractories. The industrial processes are similar in that both involve the trapping of a gas phase to cause bloating. They differ in that the bloating of lightweight aggregate occurs at lower temperatures (1000-1200°C) than ladle bricks (1350°-1470°C). Lightweight aggregate bloats during an initial rapid firing. Ladle bricks are manufactured by slow firing at 1100°C for up to 80 hours. Bloating occurs when these bricks are reheated to 1350°C . Bloating shales are those which expand twice or more times their original volume during fairly rapid firing. Commercial bloating is usually done by rotary kiln processing or sintering; in both cases the firing rate is much faster than the experimental rate (5/8°C/minute). Bloating results from the entrapment of gasses which are evolved during firing. The material must have adequate viscosity to trap gas bubbles throughout the temperature range of bloating. The finished product contains a high percentage of closed pores with a bulk density between 35-75 pounds per cubic foot. Expanded shale finds its most important use as a substitute for heavy concrete aggregate (crushed stone, sand and gravel) where low bulk density is desired property. The extent of bloating in lightweight aggregate is a function of the mineralogy and chemistry of the shale. Figure 1 shows a corner of the three phase diagram, kaolinite-quartz-(illite and chlorite). Several areas on the diagram are outlined which contain predominantly marine shales, fresh and brackish water shales, and underclays. Each sample was rapid fired and the resulting expansion was plotted on the phase diagram.

Jan 1, 1973

By Edward J. Budill

One of the most dramatic innovations in the materials handling industry has been the development of stacker cranes and automated material handling systems. The stacker crane with its many capabilities and the development of reliable industrial automation controls have combined to produce dramatic achievements in an area once characterized by inefficiency lack of management attention, and capital investment. In many areas of application however, stacker cranes and high rise storage systems have been designed and installed with insufficient thought given to their integration into the overall operations of the plant or distribution facility. This paper will look at some new and interesting breakthroughs in the integration of stacker cranes and high rise storage systems into the total manufacturing plant system. In this paper we will refer to both bridge type stacker cranes and aisle stackers. The bridge type stacker crane was developed first and was initially developed with forks or other handling devices hoisted up and down a rigid or telescopic mast. This mast system was suspended from a trolley mounted on an overhead crane bridge. Today, the primary application of the bridge type stacker is in warehousing systems for handling basic metal products such as coils, bars, sheets and plates. There is no question that the bridge type stacker has achieved notable results in storage and handling of these commodities. However, a new area for stacker crane application has been developing which in many cases over-shadows the accomplishments in the storage area. This is the application of the bridge stacker as an integral part of the manufacturing processes, or in other terms the production applications of stacker cranes. The stacker crane has a number of attributes which makes these applications very important. First, the crane bridge provides the stable platform for the mounting of machinery which can accommodate the hoisting and lateral movement of large capacity loads. Today stacker cranes are being built with capacities of up to 30 - 40 tons. The bridge cranes can easily accomplish accommodation Of these large tonnages. Secondly, the mast system provides a stable platform for the mounting of a wide variety of manipulating devices which can be used for the placement of material into manufacturing processes, the extraction of this material from these processes, and movement to other points in the process area. These attributes combined with excellent operator control and safety have led to development of the stacker crane as a production tool.

Jan 1, 1973

By K. D. Bulin

"An interesting brief history review of shovels as the primary excavating tool will permit the reader to see that immeasurable development and resources have preceded the shovel excavators which today are used extensively throughout the mining industry. With this as a background, the shovel manufacturer has the ability to utilize his resources best in those areas of shovel development in which the maximum benefits of increased reliability, performance and ease of maintenance will improve the operating rewards to the user of the equipment. The author explains the function of the shovel as a part of the material handling system. A detailed description of those areas of the shovel in which the most recent developments and major improvements have been implemented in the manufacture of the shovel excavator arc included."

Jan 1, 1973

By Blair J. R, Barrett J. R

In many underground mining applications where-dry fill is used, only a token acknowl- edgement of the fill properties is given. It is the aim of this paper to induce mining engineers to consider dry fill as an engineer- ing material rather than a mass to place in unwanted voids. Dry fill is generally cheap, inert and readily available, but it can still contribute to mining performance. In particular, the choice of the dry fill becomes more critical as stope sizes increase, controlled choked draws are used or pillar recovery introduced. Selection must be initiated from an evaluation of the role of the fill in the mining operation. In most cases the fill must be chosen before quarrying begins and an investigation must be made of available sources and appropriate quarrying methods. Some of the properties of fill are described together with evaluation techniques. A com- parison of placement conditions is limited by the complexities of material flow and degrada- tion: However, field and model tests can aid interpretation in these cases. Examples are given of aspects of dry fill selection and their incorporation in mining design.

Jan 1, 1973

By L. K. Weaver

The purposes of this Bureau of Mines report are to review the history of the domestic offshore hydrocarbon production; to project offshore oil and lease condensate production from 1971 through 1985; and to show the impact of offshore development on the onshore segment of the petroleum industry. Since 1954, offshore production has provided an increasingly larger portion of the domestic oil production. Domestic offshore oil and lease condensate production has increased from about 2.0 pct of the U.S. total in 1954 to 16.7 pct in 1970. Likewise, marketed gas production has increased from 1.0 pct of the U.S. total in 1954 to 15.0 pct in 1970. The past performance of exploration, leasing, development, and production of the offshore petroleum industry was used to make projections of offshore oil production. A comparison between onshore and offshore operations was also made. Assuming a tentative Department of the Interior offshore leasing schedule is completed by 1980, the authors estimate that by 1985, about 30 pct of domestic crude oil and lease condensate production from the lower 48 States will come from offshore areas. Currently, leasing of Federal offshore areas has been delayed due to environmental considerations. The rate at which off-shore hydrocarbons will enter the energy market will depend, to a large extent, on how soon environmental considerations are resolved. Assuming that offshore leasing will resume in the near future, U.S. offshore production of crude oil and lease condensate should be about 934 million barrels in 1985.

Jan 1, 1973

This manual provides instructions for installing, operating, and maintaining a protective canopy on the Joy Mfg. Co. loader. These instructions are based upon two actual install .at ions: one made in a mine on loader, model 14BU10-11AH, and one in the factory on model 14BU10- 11AH. The parts list and engineering drawings for the protective canopy are included at the end of the manual. And a discussion of some alternative design concepts is also included. The manual can also be used for retrofitting other loaders with similar protective canopies. Skilled mechanics can determine if the instructions herein would be applicable to the other loaders and can determine any necessary modifications if they are not.

Jan 1, 1973

This paper reviews the role of fill in mining including consolidated fill both histor- ically and currently as determined by a recent survey of the Fill Subcommittee of the Canadian Advisory Committee on Rock Mechanics (CACRM). It covers the application of fill in modern min- ing methods including mechanized cut and fill, undercut and fill, post pillar cut and fill and longhole pillar recovery between stabilized fill. An automated fill preparation plant and recent developments in rotary drilling of hydraulic fill conducting holes are described briefly. The paper also summarizes the findings of some of the important laboratory and field work carried out on the behaviour of fill in Canada, the United States and Australia and again draws on current information obtained from the Fill Subcommittee of the CACRM. Space limitations and unavailability of suitable material prohi- bit the summary of similar information from other countries.

Jan 1, 1973