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By J. Gordon Scott

The Iron Ore Company of Canada has now been operating a computer for the grading or blending of direct shipping ores for two years. This paper deals with the computer application pertaining to the grading of direct shipping ore. It consists of five sections. The first part deals briefly with a description of the operation of the Iron Ore Company of Canada; the second with the source and flow of the various data required to grade or blend ore; the third briefly outlines the computer programs used in this application; the fourth illustrates the mathematical approach used to properly blend ore. The final section briefly describes other technical computer programs.

Jan 1, 1964

By F. W. Metzger

Coal quality control in mining and mine planning has always been important and has become even more essential in recent years due to environmental considerations. The primary consumers of the sub-bituminous coals found in the Powder River Basin of Wyoming are electric utilities that require low sulfur coals to meet government air quality regulations. Electric generating plants are designed to burn coal of a specific quality, and the supplier of that coal must be able to guarantee shipments within specified quality tolerances. Over the past several years, Exxon Coal USA and, more recently, The Carter Mining Company, a division of Exxon Coal USA have established an evaluation and development program to accurately define the geology and quality of their coal properties. This requires an adequate drill hole density so that detailed correlations of the coal seam and the lithologic sub-units, of the coal seam can be made. These units must be recognizable in the core and also on geophysical logs.

Jan 1, 1981

By John J. Mulligan

Coal is found in every major geographic region throughout Alaska and in two offshore areas. Since about 1852 over 100 small mines have opened and closed. Last years production was almost entirely from one mine in central Alaska. Clearly the utilization of Alaska's abundant coal resources presents political, economic and technical problems that are far from solution. Location and Physical Features Figure one illustrates the geographical and geological similarity between Alaska and western United States. The Arctic region of Alaska generally resembles Wyoming and the Dakotas. The Brooks Range is an extension of the Rocky Mountains. The Central region of Alaska between the Brooks Range and the Alaska Range bears a general resemblance to the basin and range country of western United States. The Southcentral and Southeastern regions has a similar resemblance to the Sierra Nevadas and the west coast of the United States.

Jan 1, 1982

By Larry B. Bramlett

Regional radiometric, magnetic and geologic data point to Copper Mountain as an area of general uranium favorability. Sub-regional radiometric and magnetic data direct interest to a specific section of an overthrust Precambrian granite. Detailed magnetic and resistivity surveys in this area show local targets of interest, one of which corresponds to Rocky Mountain Energy's North Canning deposit. On the basis of these data a second and previously untested target was drilled resulting in the intersection of uranium horizons similar to those at North Canning. This integrated geophysical approach can be used for uranium exploration in geologically similar areas.

Jan 1, 1979

By G. P. Richards

RIP is the process of recovering uranium from an unclarified slime pulp which comes in contact with a moving bed of ion exchange resin, T e sand-slime separation of the acid-leach slurry is accomplished through the use of cyclones and spiral, akins type classifiers. Course sands are discarded to tailings and the combined slimes and leach liquor become the IX feed. Uranium in the IX feed is absorbed on the resin and after exhaustion the barren pulp is directed to tails, Following the uranium exhaustion cycle an eluant solution passes through the resin bed stripping the uranium from the beads, The uranium is precipitated from the clarified pregnant eluant, filtered, dried and packaged for shipment to the AEC, Normally, the ore received at the Mines Development plant is a loosely cemented sandstone containing small quantities of clay and bentonite, The ore is easily crushed and requires only a 1/3 load of rods in the rod mill to reduce the ore to grain size, Very little of the ore is recirculated by the 42" spiral classifier.

Jan 1, 1958

By Irwin H. Reiss

Gentlemen, the title of my paper is Surface Mining An Interim Land Use. Surface mining has become one of the major controversies of our time. This has happened in spite of the fact that all surface mining to date has involved only 6 million acres out of a total of 2300 million or approximately one-fourth of one percent of the total land area in the United States. I'm not going to dwell on whether peoples' perspectives are out of focus in light of the area involved, the energy crisis, national security, or the international balance of payments problem. While these things are all critically important, it is not the function of this paper to relate to them. Maybe the amount of attention attracted to surface mining is out of proportion to a lot of other things, but I don't feel that we should use that as a basis for procrastination. However, let me categorically state that anything that affects the surface of the earth is a form of land use --- be it an interstate highway, a power plant site, a golf course, a corn field, a strip mine, or the plot of ground on which your house is located.

Jan 1, 1974

By H. E. Rowen

I hope my title is not confusing; even more so that I am not. Actually pelletizing and sintering, meaning both the formation of pellets and the hardening of them, are closely related to each other and to phenomena of nature. Figure. 1 This many-celled porous structure, frozen as it was at the fusion temperature and was being frothed by fast-moving gases, may be considered a typical piece of sinter. The same structures have been found in natural ores.

Jan 1, 1962

By D. C. Sisti

A paper was presented during the 1970 SME Fall Meeting on the Stinson Preparation Facilities by representatives of Beaver Creek Consolidated Cool Company and Heyl & Patterson, Inc. This paper summarized a combined approach to development of a flow diagram and selection of cleaning equipment required to produce a uniform metallurgical coal at maximum recovery with special emphasis on sulphur reduction. These facilities were located in the Elkhorn. Coal Fields of eastern Kentucky and, in particular, the area of Wayland, Knott County, Kentucky, where approximately forty-five- million tons of Elkhorn No. 3 coal could he recovered. The facilities incorporated a Bradford Breaker for reduction of the ROM coal to minus 1-1/2 x 0, 6000 ton-raw coal storage, preparation plant, water clarification and thermal drying facilities, clean coal storage and a 4000 TPH unit train loading facility.

Jan 1, 1973

By John S. Owens

The National Steel Pellet Project and the Butler Taconite Project are operated by The Hanna Mining Company in the vicinity of the towns of Keewatin and Nashwauk, on the western Mesabi Range. Production began in 1967, after seven years of exploratory and development diamond drilling and reconnaissance magnetic surveys, Previously, direct shipping hematitegoethite ores and gravity concentrates had been produced in the area from numerous open pits and several underground mines since the start of the century. Total shipments of these oxidized ores amounted to more than 200 million tons, but at the present time such reserves are nearly exhausted, and there are no mining operations in the Keewatin-Nashwauk area except at the two taconite projects. The locations of all of the present taconite operations on the Mesabi Range are shown in Figure 1, extending for a distance of about seventy miles from the Butler plant to the Dunka River area. The Butler and National plants have a combined rated capacity of 4.4 million tons of pellets. Their reserves cover a combined strike length of about eight miles on the Biwabik iron formation. All of the intervals between present taconite operations on the Mesabi are potential sources of additional magnetic taconite; in particular, exploration and economic studies have been carried out by Jones and Laughlin Steel Corporation in the Biwabik area between Aurora and Virginia, and by Pickands Mather and Company in the Hibbing area. However, west of the Henna and Butler holdings, it appears unlikely that magnetic taconite exists in commerical quantities at economic depths due to extensive oxidation of magnetite to hematite.

Jan 1, 1968

By R. E. Coleman

Infrared spectroscopy, employing the internal reflection method in conjunction with solvent extraction techniques, was used to study surface reactions between aqueous potassium ethyl xanthate and both sphalerite and precipitated zinc sulfide each activated with aqueous copper sulfate. It was determined that reactions occurring on the sphalerite and zinc sulfide surfaces produce the reaction products ethyl dixanthogen and cuprous ethyl xanthate, some of which are ad¬sorbed on the mineral surfaces. According to infrared spectra showing the reaction to form these compounds, the ratio of cuprous ethyl xanthate to ethyl dixanthogen adsorbed is directly related to pH of the flotation solution.

Jan 1, 1967

By B. W. Madsen

Experimental results obtained from large scale (7 tons), long-term (500 days) leaching of low tenor copper sulfide ores were interpreted by a geometric model involving the movement of a reaction zone through the ore fragments. The postulated leaching mechanism involved mixed kinetics and included diffusion of the reacting species through the host rock and a chemical reaction at the surface of the mineral particles. Ore properties which were considered were ore particle size and shape, grade of ore, and mineral content. Excellent agreement between the mixed kinetic model and the laboratory leaching results was obtained when minus ½ inch ore particles were not included in the leach. Also, a satisfactory prediction of copper recovery from plus ½ inch ore with a different particle size distribution was made; however, it was necessary to modify the shape factor in the model. Predictions of copper recovery from an ore sample which included the minus ½ -inch fine fraction and leaching for 460 days was 56.5 percent, and the recovery from leaching was 47.0 percent. The presence of fines caused channeling and uneven solution distribution and inhibited the leaching rate.

Jan 1, 1974

By W. J. Nelson

Detailed underground geologic map- ping at a scale of 1:1200 has been carried out at the Crown II Mine of Freeman United Coal Mining Company, which operates in the Herrin (No. 6) Coal Member. The roof sequence, upward from the coal, includes (1) soft, medium- to dark-gray shale; (2) hard, black, fissile shale; (3) argillaceous nodular-bedded limestone, and (4) fine-grained, shaly, water-bearing sandstone. The first unit is highly lenticular, and any or all may be missing at a given locality. The sand- stone has a sheet facies and a channel facies. The Herrin Coal is eroded in channels near the Crown II Mine. Structural features mapped at Crown II include normal and strike-slip faults of small displacement, "slips" and clay dikes, and limestone "bosses." Less stable roof and wet con- ditions are encountered where the limestone is thin or missing or where it is broken by natural fractures or by artificial openings that inter- sect the water-bearing strata above the limestone. Geologic mapping of the underground workings has allowed us to predict faults, fracture zones, and channels ahead of the face for this mine. Some lithologic and structural patterns apparently are random and cannot now be projected. Conventional exploratory drilling is entirely inadequate to map faults or lithology of the roof, but it does indicate the range of lithologic variability, which can be used to project needs for roof sup- ports. Drilling also is useful In locating channels and in mapping regional variation in thickness and facies of the sandstone.

Jan 1, 1980

By E. M. Haynsworth

The disposal of phosphatic clays has presented a problem to the phosphate industry since the mining of phosphate rock first began. As the flotation process was introduced in the late 1920's, the problem of clay disposal was increased significantly since clay is present in proportionally greater quantities in reserves yielding flotation concentrates. Because of their physical character and the tremendous surface area per unit volume, these clays have the characteristic of retaining large volumes of water as they are slurried during processing. The phosphatic clays with which we are dealing consist primarily of apatite, wavellite and montmorillonite. In the beneficiation process, we remove the -150 mesh material as waste. However, the particles are essentially smaller than -325 mesh, and more than 70% are smaller than three microns. The disposal of clay and the recovery of a portion of the water require settling areas with a capacity ranging up to 2 cubic feet for each cubic foot of phosphate matrix mined. According to a recent study by the Bureau of Mines, the average cost for disposal of these wastes is 24.5 cents per ton of, product (U. S. Bureau of Mines Circular 8404). This is a major cost of phosphate rock production.

Jan 1, 1970

By S. C. Gambrell

The practice of roof bolting in world-wide mining activities is very well known, having been used extensively for over 50 years. The theory of roof bolting, however, is extremely complicated, and only recently have investigators attempted to explain the theory. Discussions of the mechanics involved usually originate with actual experience gained in the use of roof bolts. The use of roof bolting in mines has grown dramatically during the period after World War II. Other scientific techniques have emerged in mining research in the same period. Included in these techniques is the study of rock mechanics, which has now developed into an impressive research effort. Various means of analysis have been utilized in rock mechanics, most of which reduce rock to an isotropic, homogeneous medium that could be easily analyzed. Because of the inherent nature of rock, direct research methods frequently are not certain to provide satisfactory results, whereas indirect methods must idealize a given set of conditions in order to be useful. One of the indirect research methods is the photoelastic technique, the theory of which is widely known and needs no elaboration. This technique has been used extensively to examine the state of stress around underground openings of various shapes in certain types of strata, and under various configurations (1,2,3,4,5). Much of the theory used now in the design of underground openings is based on photoelastic evaluation. Unless rigorously applied, how- ever, the photoelastic technique is at best a qualitative means of evaluation. It is useful, however, for unusual examples which can be more or less easily analyzed to obtain the overall state of stress which could not be determined by other means. Little work has been done in the photoelastic analysis of rock bolting, mainly because direct research techniques have proven useful.

Jan 1, 1970

By Robert F. Conley

In the mining, manufacturing and application of inorganic pigments, dispersion contributes significantly. This is especially true with mineral pigments because of the variety, in slurry operations required for their processing. Such operations include any of the following: (1) mine-transport (2) wet grinding (3) flotation/beneficiation (4) wet magnetic separation (5) selective floculation (6) size classification (7) chemical processing (8) spray drying Dosage levels and general economics of dispersant use are broadly variant, being dependant upon the agents employed, from the simplist, i.e., sodium silicate or sodium carbonate, to the more complex, as polyacrylates and organo-phosphates. In certain unit processes the dispersant must exhibit unusual chemical stability and persistence, e.g., in protracted pigment slurry shipments. In others, the agent should be fugitive to prevent secondary reactions from occurring, e.g., with high temperature calcination where alkali salts can act as aggregation fluxing agents.

Jan 1, 1985

By E. C. Wilson

The knowledge concerning the lubrication of open gearing for mining machinery has contained many unknowns and at its best has relied to a great degree on a "Rule of Thumb" procedure. It will be within the scope of this paper to explain what we have learned to date and what must be learned in the future. The results in the lubrication of open gearing have spanned the spectrum of unsatisfactory to satisfactory. With the advent of larger mining machinery, we are faced with the necessity of a more thorough knowledge of open gear lubrication. We have avail- able, better steels for the gearing, advanced technology and machinery for cutting proper tooth profiles, and better means of aligning the teeth in the gear train. This has made it possible to transmit more horsepower through the same size gear set than ever before, if we have the proper lubrication to complement the factors previously mentioned. We have set up computer programs which can calculate the data fox the tooth forms, the correct operating center distances, the contact stresses, the bending stresses, and the PVT factor of the gear teeth. This program does not, at the present, have sufficient data available to calculate the type of lubricant which should be used.

Jan 1, 1968

By P. Bartel

Coal cleaning can be effected by the bacterium Sulfolobus acidocaldarius, which in oxidizing sulfur and dissolving mineral matter requires carbon dioxide and oxygen; carbon dioxide as a carbon source and oxygen as an electron acceptor. The desulfurization of coal by thermophilic bacteria under elevated partial pressures of carbon dioxide and oxygen was studied at a total pressure of 1 atm. The partial pressure of carbon dioxide was varied over the range 0.00032 to 0.33 atm (0.00032, 0.007, 0.10, 0.33 atm), and the partial pressure of oxygen was varied over the range 0.14 to 0.40 atm (0.14, 0.21, 0.30, 0.40 atm). The maximum rate of coal desulfurization increased by 32%, from 9.0 to 11.9 mg S/1 hr, as air was enriched in carbon dioxide from its atmospheric level of 0.00032 atm to 0.10 atm. Enrichment with carbon dioxide up to 0.10 atm, at constant oxygen partial pressures, increased the desulfurization rate, but enrichment to 0.33 atm caused the rate to decrease. At constant carbon dioxide partial pressures, the desulfurization rate was maximum at oxygen partial pressures of 0.21 and 0.30 atm. At higher (0.40 atm) and lower (0.14 atm) oxygen partial pressures the rate decreaed by 9 to 20%. The desulfurization rate decreased by 58X, from 9.0 to 3.8 mg S/1 hr, when the air pressure was increased from 1 atm to 3 atm. The effects justify an economic analysis during design and operation of a commercial air feed in a process to desulfurize coal by microbial action.

Jan 1, 1986

By Edward F. Oxford

The area described in this paper lies along the inner margin of the Coastal' Plain in Twiggs County, near the exact center of the State of Georgia. Twiggs is one of four counties which produces approximately 75 per cent of the nationals output of kaolin used in the paper trade. In this vicinity the land surface is characterized by coastal plain hills with elevations ranging from about 250 feet, above mean sea level in the flood plain of: the Ocmulgee River to about 550 feet above mean sea level on the hill tops. Surface drainage in the area is southwestward to the Ocmulgee River, the tributaries of which have dissected the land surface exposing thick sections of the upper parts of the hills of Eocene (Ocala Limestone and Barnwell formation) limestone, sand, marl and clay, and in the lower parts of the hills Cretaceous (Tuscaloosa Formation) kaolin, kaolinitic clay, sandy clay, sand and, gravel. The contact between these two principal groups of geologic units is rather easil distinguished as the top of the kaolinitic beds. It is described in detail and mapped in published geologic reports for the area (LaMoreaux, 1946).

Jan 1, 1968

By Haydn H. Murray

Kaolin is an important industrial mineral because it exhibits desirable properties in many applications and because of its relatively low cost, Approximately 2,000,000 tons of kaolin from Georgia and South Carolina are processed and used commercially in the United States each year. Strictly defined, the name kaolin is applied to a group of hydrous aluminum silicates of which the mineral kaolinite is the most common. Kaolinite has such desirable properties as natural whiteness, chernical stability, non- abrasiveness, and very fine particle size. Kaolinite particles are characteristically thin, flat, and hexagonal in outline. The particles range in size from submicron to as much as 40 microns (equivalent spherical diameter). In addition to the general properties mentioned in the first paragraph, it is soft, has low viscosity at high solids content in many systems, is readily wet and dispersed in water and some organic systems, and can be produced with a controlled particle size distribution. Some of the important physical constants of kaolin are: specific gravity, 2.60; index of refraction, 1.56; hardness (Mohs scale), 2; fusion temperature, 1850°C; dry brightness, 78-92 percent.1

Jan 1, 1965

By Harold E. Rowen

The listed title of my talk to-day is "MODERN ON STRAND SINTER COOLING". Perhaps it should he ve been "COMPLETION OF SINTERING ON THE STRAND" as the two are synonymous. By the very nature of the DWIGHT-LLOYD SINTERING PROCESS partial cooling on the strand is always present, but not completion of sintering and cooling on the strand. I have mentioned the Dwight-Lloyd process just to be certain the type of sintering under discussion is fully identified because some of the basic mechanisms of sintering occur in various pyro-processing of fines lying in close quiescent contact, such as powdered metals practices, some types of pellet induration, firing of briquets, or other compacts, where the entire bed is brought to, and held at, the high reaction temperatures of sintering. Figure 1, The continuous sintering process as originally conceived consisted of intimately mixing carefully proportioned burdens, placing them in a comparatively thin, draft permeable layer, on a moving grate and igniting the surface while drawing sir through the bedded burden. The moving grate was advanced slowly as the line of burning fuel travelled from the surface to the bottom of the bed and no more fire zone could be seen.

Jan 1, 1973