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By C. Grua, M. Gottlieb, E. M. Wewerka

The Purpose of this paper is to present an overview of research underway at the Los Alamos Scientific Laboratory to investigate some of the more attractive options for controlling trace element contamination of coal refuse drainages. * The control methods under consideration include chemical and physical methods to immobilize or remove undesirable contaminants prior to refuse disposal, the treatment of refuse disposal sites with attenuating agents to prevent the discharge of contaminated water, and the direct treatment of refuse drainage as it emerges from the refuse disposal site. The results from these laboratory studies suggest that many of these techniques are technically feasible for controlling trace element contamination of refuse dump drainage.

Jan 1, 1982

By L. C. Aycock, J. Hunter, P. M. Lyons

In view of the unfavorable discovery trend that has set in during the past few years, it seems permissible to infer that the large, more easily found crude reserves in Louisiana are now known. Without doubt, many new producing areas will be located, but in the light of development during the past few years the majority of new areas probably will be found at greater depths and from relatively poorer sands. f Although sufficient reserves exist in Louisiana to last at the present rate of production for a considerable period, additional reserves must be found in more intensive development of the presently known structures. In order to ensure the greatest ultimate recovery from such structures, the most advanced technical methods must be employed in their exploitation. Wherever possible, cycling and repressuring plants should be installed. 'here are presently in Louisiana, especially in south Louisiana, a great many fields that contain gas-condensate reservoirs. These reservoirs cannot be produced for their liquid hydrocarbon content under present conditions without wasting an enormous quantity of gas and creating underground waste. Although some of these reservoirs are being produced, such production must be considered in the nature of a salvage operation rather than as a sound economic proposition. Such reservoirs, however, can become profitable ven- tures through the use of cycling and repressuring plants. Cycling operations now operating in Louisiana have increased the ultimate recovery from gas-condensate reservoirs anywhere from 10 to 30 per cent. Cycling operations will also provide a considerable reserve of gas, without which Louisiana cannot hope to develop any program of industrialization. During the past year, Louisiana attained the rank of third among the oil-producing states of this country. With a proper program of exploitation and development, and with emphasis on conservation, Louisiana can maintain this position for a great many years. Production On Dec. 31, 1943, oil and/or gas were being. produced in 52 parishes, or 81 per cent of all the parishes in the state. Thirty-three of the parishes produced oil and gas, 14 produced oil, and 5 produced solely gas. Tensas Parish in north Louisiana and Assumption Parish in south Louisiana formerly contained no producing fields but during 1943 joined the ranks of the producing parishes. Twenty-three new fields, including one rediscovery, were found during 1943-—a rate of discovery almost comparable to that of the preceding year. Eleven of these new discoveries were either gas or gas-condensate fields. Thus, the trend of development in finding new reserves was also comparable to that of 1942. Many reasons of considerable merit have been advanced to account for the discouraging lack of crude-oil reserves found during the past year. None are, however, completely satisfactory.

Jan 1, 1944

By J. Hunter, P. M. Lyons, L. C. Aycock

In view of the unfavorable discovery trend that has set in during the past few years, it seems permissible to infer that the large, more easily found crude reserves in Louisiana are now known. Without doubt, many new producing areas will be located, but in the light of development during the past few years the majority of new areas probably will be found at greater depths and from relatively poorer sands. f Although sufficient reserves exist in Louisiana to last at the present rate of production for a considerable period, additional reserves must be found in more intensive development of the presently known structures. In order to ensure the greatest ultimate recovery from such structures, the most advanced technical methods must be employed in their exploitation. Wherever possible, cycling and repressuring plants should be installed. 'here are presently in Louisiana, especially in south Louisiana, a great many fields that contain gas-condensate reservoirs. These reservoirs cannot be produced for their liquid hydrocarbon content under present conditions without wasting an enormous quantity of gas and creating underground waste. Although some of these reservoirs are being produced, such production must be considered in the nature of a salvage operation rather than as a sound economic proposition. Such reservoirs, however, can become profitable ven- tures through the use of cycling and repressuring plants. Cycling operations now operating in Louisiana have increased the ultimate recovery from gas-condensate reservoirs anywhere from 10 to 30 per cent. Cycling operations will also provide a considerable reserve of gas, without which Louisiana cannot hope to develop any program of industrialization. During the past year, Louisiana attained the rank of third among the oil-producing states of this country. With a proper program of exploitation and development, and with emphasis on conservation, Louisiana can maintain this position for a great many years. Production On Dec. 31, 1943, oil and/or gas were being. produced in 52 parishes, or 81 per cent of all the parishes in the state. Thirty-three of the parishes produced oil and gas, 14 produced oil, and 5 produced solely gas. Tensas Parish in north Louisiana and Assumption Parish in south Louisiana formerly contained no producing fields but during 1943 joined the ranks of the producing parishes. Twenty-three new fields, including one rediscovery, were found during 1943-—a rate of discovery almost comparable to that of the preceding year. Eleven of these new discoveries were either gas or gas-condensate fields. Thus, the trend of development in finding new reserves was also comparable to that of 1942. Many reasons of considerable merit have been advanced to account for the discouraging lack of crude-oil reserves found during the past year. None are, however, completely satisfactory.

Jan 1, 1944

By E. H. Bronson

PROPERTY of Malartic Gold Fields Ltd. is situaated in the great clay belt in the northern part of the Province of Quebec. This belt represents the floor of the glacial lake Barlow-Ojibway. The clay blanket has a gently rolling, almost flat surface, with here and there projecting knobs and ridges that outline the large irregularities of the surface on which the clay was deposited. At irregular intervals glacial eskers dominate the landscape. The ore-bearing country rock is covered by strata of clay, sand, and silt to a depth varying to 40 ft. There are serious structural problems when it is necessary to place loads of unequal intensities on this surface to support buildings and machinery for a modern mining plant. Earlier mining companies and their engineers paid little attention to the science of soil mechanics, partly because they believed it unnecessary and partly because they knew little of the subject. The results are evident in some of the tottering structures in older camps. Careful analysis of soil problems is well worth-while, since cost of foundations may vary from 20 to 50 pct of the final cost of a structure. Low operating and maintenance costs can be achieved only in this way.

Jan 11, 1957

By W. C. PAGE

HARVEY S. MUDD has the unusual distinction of having virtually inherited a Directorship in the -A.I.M.E., for he was appointed to the Board to fill the unexpired term of his father in 1926. Since then he has served as a Director continuously until 1936, and now he is a candidate for Vice-President. One of the first words that young Harvey tried to say was "ore," for he was born in Leadville, Colorado, in the heyday of that camp, where Seeley W. Mudd for years ran the Small Hopes mine. Stanford and Columbia gave him his mining education, and the Shattuck-Arizona, at Bisbee, his first job. Afterwards he examined many

Jan 1, 1937

By Peter G. Chamberlain

Many mining engineers considering in place leaching for the first time are uncertain as to how to evaluate ore bodies for potential leachability. Evidence presented in this report emphasizes the critical role of permeability in such evaluations. Whether an engineer is considering leaching "tight" formations typified by the porphyry copper deposits of the southwest or the permeable uraniferous sandstones of Texas and Wyoming, permeability measurements are the keystone of any testing program. Permeability tests range from cheap and easy to highly expensive and sophisticated operations. Constant head, variable head, and pumping tests all have application in evaluating ore bodies for in-place leaching. Costs of these tests will not unduly deflate the pocketbooks of most mining companies. The basic procedures for selecting and running these field tests--including preparing suitable wells--are reviewed for the benefit of newcomers to in-place leaching.

Jan 1, 1979

By Lyle D. Randen

With the environmental movement beginning in the late 1960's came a deluge of permit requirements for the mining industry. Coal mining has been one of, if not the most, severely impacted of the mineral industries as a result of the passage of the Federal Surface Mining Control and Reclamation Act of 1977. Numerous provisions of this Act and numerous regulations developed under authority of the Act are being challenged in differing levels of the judicial system across the United States. Such court cases have had varied success. Numerous other regulatory programs that are not quite as dramatic as the SMCRA have presented an unending regulatory problem for mining operators. My comments in this presentation relate primarily to the major Federal and State agencies and their legal responsibilities which we in the coal mining industry must address in order to receive authority to construct and operate surface coal mines in the State of Wyoming. A list of the Federal and State agencies one could deal with in an application is as follows: 1. Bureau of Land Management (BLM). BLM is responsible for deciding where and when to lease federally owned coal and for establishing terms and conditions for leases. BLM also has some control over surface reclamation on federal land, i.e. regrading to eliminate highwalls, covering of spoils, maximum extraction of coal to limit future disturbance, contemporaneous reclamation, etc. BLM is also responsible for designation of federal lands unsuitable for all or certain types of surface coal mining operations. 2. Geological Survey (USGS). USGS coal mining responsibilities apply only to Federal and Indian lands and concern compliance with production requirements including diligent development, minimum production levels, royalty payments and resource protection, and

Jan 1, 1983

By Robert D. Pehlke, Robert G. Blossey

The solubility of nitrogen in liquid cobalt and a number of dilute cobalt alloys Was measured in the temperature range 1550" to 1700°C at nitrogen pressures to 1 atm. At 1600°C and 1 atm nitrogen pressure, the solubility in pure cobalt is 0.0047 wt pct [3.8 cu cm (stp) per 100 g Co]. The standard free- energy change for the solution reaction 1/2 N,(g) = gout pct in Co) is iF - 10,000 + 5.24 T cal per g atom N. The alloying elements Cv, Cu, Mo, Nb, Tu, W, and V increase the nitrogen solubility, while Al, Fe, Ni, and Si decrease the nitrogen solubility. THE solubility of nitrogen in cobalt was studied previously by Sieverts, Busch and Dodd,2 and Schenck, Frohberg, and Graf.3 Sieverts investigated the solution below the melting point of cobalt, and Busch and Dodd worked with the liquid metal; however, neither study found any solubility for nitrogen in cobalt. Schenck et al, reported a solubility of 0.005 wt pct N in cobalt at 1600°C. Seagle et al. 4 reported residual nitrogen in cobalt after electron-beam melting, although no reasons were ventured for the presence of this interstitial impurity. This investigation was undertaken to clarify these inconsistencies, and to provide additional data on atomic interactions in dilute metallic solution. EXPERIMENTAL PROCEDURE This study was well-suited to the Sieverts' method, which has not changed significantly since its introduction by Sieverts. 5 The apparatus was of the same design as that described by Humbert and Elliott, 6 with a reaction bulb similar to that reported by Weinstein and Elliott. 7 The buret was not water-jacketed, but the measured gas volumes were corrected for small changes in room temperature. The melt temperature was measured by a disappear ing-filament optical pyrometer sighted through a prism onto the melt surface. Temperature calibration was made based on a measurement of the melting point of pure cobalt taken as 1495°C. The difference between the reciprocal of the observed and the true temperatures was assumed to be a constant, neglecting the changes in emissivity with small additions of alloying elements. The total error in gas-volume measurement caused by accuracy limitations in reading the mercury level in the buret, variation in ambient temperature, and variation in melt temperature was about 0.5 cu cm. This represents approximately 10 pct of the total solubility, and is a larger relative error than in previous studies6-' because of the small nitrogen solubilities encountered in the present investigation. The source and purity of the materials used are listed in Table IA. Recrystallized alumina crucibles were used throughout the investigation. Examination of the crucibles after solidification of the melts showed no reaction or penetration. Alloying of the cobalt melt was accomplished with the dropping technique described by Humbert. 6 The investigation was started using cobalt from African Metals Corp. in shot form, but this material was not of sufficient purity and did not yield consistent solubility results. Sherritt Gordon Mines Ltd. cobalt was then used throughout the investigation. In experiments involving alloying elements which could react with oxygen dissolved in the melt, the cobalt was further refined by annealing at 1400°C in a dry-hydrogen atmosphere. This treatment, described by Woolley and Pehlke, 8 markedly reduced the oxygen content. The oxygen and nitrogen analyses of the cobalt used in this study are presented in Table IB. RESULTS Hot Volume. The hot volume was measured prior to each run and was 50 to 55 cu cm (stp) at 1600°C. It increased linearly with increasing pressure and decreasing melt temperature. Pure Cobalt. Measurements of the solubility of nitrogen in pure cobalt and the temperature coefficient of solubility are summarized in Table 11. At 1600°C and 1 atm nitrogen pressure, the solubility was found

Jan 1, 1967

By Thomas Harris

This paper. was written in conjunction with the work being undertaken by the Technical Committees on Classification of Coal, and an effort has been made to compile information relative to the use of coal for stationary steam generation in order to use this information to assist the Committee on Classification of Coal for the ultimate purpose of elimination of losses both by the' reduction of indivi-dual effort and waste in the consumption of material. Under the auspices of the National Association of Purchasing Agents, a questionnaire was drawn up to develop this information from stationary steam plants throughout the United States. in order to consolidate the information de-veloped from the many hundreds of boiler tests on coals consumed by various coal¬burning equipment. These questionnaires covered: 1. The company reporting, location and method of delivery to the plant. 2. Complete coal date, including description of coals used (with. sufficient space to- include first, second and third, preference) on--source of coal used,- complete-analysis and factors affecting choice of, coal used. 3. Plant data, divided into - A. Hand fired, B. Overfeed stokers,. . C. Underfeed stokers, D. Traveling grate stokers, E. Pulverized coal, and included complete description of furnace data, draft data, coal-burning rate, type of stoker, type of pulverizer, efficiency date and remarks.

Jan 1, 1933

By Walter A. English

The four papers making up this symposum have been prepared especially for those who have no knowledge of seismograph prospecting. To many people mathematics is a formidable subject, and many are discouraged from studying seismograph prospecting under the mistaken assumption that the mathematical requirements are severe. In the papers presented here there is not a single mathematical equation. We believe that considerable competence in dealing with some of the most important problems of this work can be attained without any mathematical training whatever. At the present time, there is a real need for interpretation of results by persons thoroughly competent to bring geologic experience and imagination to bear on data that are subject to multiple interpretation from a strictly physical viewpoint. Likewise, those charged with the responsibility of planning seismograph exploration campaigns would do well to become familiar with as much as possible of the technical aspests of the work. They would then be in better position to judge of its success in individual cases. It has often been said that the seismograph is a new structure-finding tool for the geologists to use. Using a tool and using its product are two different things. One does not use an automatic screw-threading machine when he buys a box of screws at the hardware store. Neither does the geologist

Jan 1, 1940

By Walter A. English

The four papers making up this symposum have been prepared especially for those who have no knowledge of seismograph prospecting. To many people mathematics is a formidable subject, and many are discouraged from studying seismograph prospecting under the mistaken assumption that the mathematical requirements are severe. In the papers presented here there is not a single mathematical equation. We believe that considerable competence in dealing with some of the most important problems of this work can be attained without any mathematical training whatever. At the present time, there is a real need for interpretation of results by persons thoroughly competent to bring geologic experience and imagination to bear on data that are subject to multiple interpretation from a strictly physical viewpoint. Likewise, those charged with the responsibility of planning seismograph exploration campaigns would do well to become familiar with as much as possible of the technical aspests of the work. They would then be in better position to judge of its success in individual cases. It has often been said that the seismograph is a new structure-finding tool for the geologists to use. Using a tool and using its product are two different things. One does not use an automatic screw-threading machine when he buys a box of screws at the hardware store. Neither does the geologist

Jan 1, 1940

By R. T. Gallagher, C. G. Brennecke

This paper is the result of a research program entered into cooperatively by the General Reinsurance Corporation and Lehigh University in January 1944. The research program was instituted to find a more positive method to determine the presence of hazardous roof conditions in mining operations. The co-authors, together with Mr. R. D. Currie, Engineer for the General Reinsurance Corporation, started working on the project in January 1944, first undertaking a library search; second, a preliminary study based on some existing equipment; third, the design of new and more suitable equipment; and finally, the field testing of equipment and methods. PURPOSE Any study of the accident statistics of mining operations will disclose the rather startling fact that approximately 50 to 60 per cent of all fatal underground accidents in the anthracite and bituminous mines are caused by falls of roof and coal, the metal and nonmetal mines showing only a slightly smaller percentage. Advancements in safety engineering have produced definite results in the decrease of accidents due to blasting, haulage, electricity, and explosions but no such decrease is shown in those caused by falls

Jan 1, 1946

By Norman J. Gibbs, John Sroka

INTRODUCTION At the point a company decides to begin mine development and wishes to convince lending institutions that the proposed operation will return their borrowed funds, plus interest, over the terms of the loan, communications between lender and borrower are crucial. The importance of the mine feasibility presentation should not be underplayed, especially as new projects continue to increase in size, complexity, and cost. While the content and emphasis of a report to the lender will vary according to the particular project and type of debt financing sought, there is a general base of information upon which all such studies are built. THE PROJECT'S TECHNICAL ASPECTS Here, the object is to satisfy the lender that he will not be unduly exposed to technical risks as a result of the physical scope of the project. Reserves The feasibility report submitted to financial institutions should include an adequate description of the geologic setting, mineralogy, ore types, and reserves broken down into such recognized categories as proven/probable/possible or measured/indicated/inferred. Rather than a bald statement of reserves, lenders prefer to have detailed information on: History of exploration Drilling, both percussion and core, with core recovery, drill hole spacing, analyses, and continuity of mineralization Bulk sampling, with core assay comparisons Overburden, with stripping ratios Specific methodology of reserve calculation, and Geologic reserves vs. mineable reserves. As a rule of thumb, a lender would prefer to see that reserves in the proven class alone are sufficient to support operations at the design rates until the borrowed funds are repaid. (See also Schreiber above in this Chapter.) Mining The rationale for adoption of a particular mining technique should be presented as well as descriptions and justifications for: Preproduction development Preliminary mine plan, with forecasts of grades and material movements Geotechnical test work which influenced decisions Mining recoveries and efficiencies Major equipment, with type, model, rating life, spares, replacement schedules, utilization, and productivity Manpower requirements and work schedules Design assumptions Ore stockpiling and blending Environmental requirements, and Waste disposal Processing If a new ore body is to be developed or a new process used, it is important to provide details of test work, scale up, and extrapolation factors. A basic process description with a summary of the studies which justify the intended processing route should be included with the following data:

Jan 1, 1985

The Committee on Nominations will welcome from members of the Institute suggestions for the offices which are to be filled by election in February, 1018, and which are as follows: One officer, known as Director and President. Two officers, known as Director and Vice-President. Five officers, known as Director. The attention of members is called to Articles V and. VII of the Constitution, and to By-Law VIII, which reads as follows: "The geographical districts to he considered by the Committee on Nominations shall be as follows, until otherwise ordered by the Board.

Jan 8, 1917

By W. A. Boyer

Mine hoisting ropes can be loaded to capacity only when the strength of each component is exactly known. Characteristic curves provide this information. When load and rate of acceleration are specified for an individual rope, the characteristic curve assumes a predetermined shape. The factor of safety is the value derived by dividing the breaking strength of the rope by the total stress on the rope where it goes over the sheave wheel. Total stress is made up of the weight of skip and cage, weight of ore, weight of rope between sheave and rope clevise or attachment, friction load, and acceleration force. Bending stresses are neglected in this discussion, as sheaves and drum diameters are assumed to be large enough to reduce these stresses to a negligible value.

Mar 1, 1956

By Clark A. Sumner, D. Arthur Burnham

A process for recovery of greater than 99% of the copper contained in acid leach solutions by sulfide precipitation using hydrogen sulfide as a hydrometallurgical reagent has been developed. The process incorporates the concept of hydrogen sulfide addition to recycled copper sulfide solids in a turbulent flow area where further precipitation or agglomeration occurs to increase the effective particle size of the copper sulfide precipitate. Because the recycled solids provide a larger number of particles upon which momentary excesses of hydrogen sulfide are absorbed, oversulfidization of the product is prevented. Copper sulfide precipitates produced in this manner in a laboratory test reactor showed greatly improved physical characteristics compared to copper sulfide precipitates obtained by conventional direct precipitation in which H2S is bubbled directly into acid leach liquor. Copper sulfide precipitates were evaluated and compared by use of filtration tests and settling rate studies. Electron microscopic examination of the solids confirmed the presence of larger particles in reactor-precipitated copper sulfide. Flotation was examined as an alternative to filtration for recovery of CuS precipitates and was found to achieve complete CuS removal without addition of collector or frothing reagents in a period of 2 min. In the same test reactor, a rapidly floatable CuS precipitate was also formed by mixing H2S with acid liquors used to leach crushed copper oxide-copper sulfide ore (LPF process). In the presence of gangue from the crushed ore, flotation of both natural and reactor-produced copper sulfides resulted in recovery of better than 90% of the copper contained in the crushed ore.

Jan 1, 1974

By H. W. Smith, A. K. Bjerring

A nonlinear dynamic model for a flotation cell is developed, using a number of simplifying assumptions, the most important of which is that of essentially complete liberation in the feed material. Using this model, a complete dynamic model for a flotation circuit is developed and calibrated against steady- state process data. The dynamic response of the circuit to disturbances in input feed rate and composition is simulated, as is the response of a linearized and simplified model on which control design might be more easily based. Preliminary results indicate the practicability of the modeling technique. However, difficulties in matching steady-state operating conditions in one process stream, and the apparent importance of recycle streams as indicators of process operation, indicate that inclusion of at least one species of middling particle in the model should be considered.

Jan 1, 1969

September 28, 1915. The Nominating Committee of the American Institute of Mining Engineers has the honor to present the following nominations for officers of the Institute to be voted for at the 1915 Annual Meeting: For President: L. D. Ricketts District 0 For Vice-Presidents: Karl Eilers District 0 James MacNaughton District 4 For Directors: Thomas B. Stearns District 7 Charles F. Rand District 0 Charles W. Goodale District 5 Edwin Ludlow District 2 George D. Barron District 0 F. W. BRADLEY, Chairman.

Jan 11, 1915

By Chester A. Rowland

INTRODUCTION Comminution is generally a feed preparation step for subsequent processing stages; exceptions being when a final product such as aggregates, specification sand, Portland Cement, and similar products is produced. Grinding, the fine product phase of comminution, requires a large capital investment and frequently is the area of maximum usage of power and wear resistant materials. Grinding is most frequently done in rotating drums utilizing loose grinding media, lifted by the rotation of the drum, to break the ores in various combinations of impact, attrition and abrasion to produce the specified product. Grinding media can be the ore itself (autogenous grinding -- primary and secondary), natural or manufactured non-metallic media (pebble milling) or manufactured metallic media -- steel rods, steel or iron balls. This chapter will discuss general mill design and the specific design and application of the following types of tumbling grinding mills. [Overflow Rod Mills Figure 1 Peripheral Discharge Rod Mills Figures 2 and 3 Compartment Mills Rod and Ball Figure 6 Ball Figure 6a Pebble Mill Figure 6b Overflow Ball Mills Figure 8 Diaphragm (Grate Discharge) Ball Mills Figure 9] I. GENERAL MILL DESIGN A. Liners The interior surface of grinding mills exposed to grinding media and/or the material being ground are protected from wear and corrosion by rubber, metallic, a combination of rubber and metallic, or non-metallic wear resistant materials. B. Drives Economics at the time of plant design and mill purchase determine the drive to be used. The simplest drive is the low speed synchronous motor with speeds in the range of 150 to 250 RPM connected to the mill pinion-shaft by either an air clutch or flexible coupling.

Jan 1, 1982

After months of negotiations, the U. S. has agreed to buy between 6000 and 7000 long tons of Bolivian tin now stockpiled at Peruvian and Chilean ports, at $1.175 per lb, f.o.b. South American Ports. Harry A. McDonald of the Reconstruction Finance Corp. signed the contract with Victor Andrade, Bolivian ambassador. The Mercantile Metals and Ore Corp., of New York City, acted as the agent of Bolivia's Banco Minero in negotiating the deal. The contract is a short term one. Throughout the talks, the U. S. refused to make a long term agreement because of the possibility that Bolivia will soon nationalize its mines. The Bolivians desired to sell the U. S. 18,000 tons during a one-year pact. The price agreed upon is roughly the same as with Malayan producers. In the meantime, American Smelting & Refining Co., signed over control of its operations to the Bolivian Government. The formal act of leasing the mines to the Bolivian Government follows the announcement last July by the company that it was closing operations because of high costs. Contract terms were not disclosed.

Jan 1, 1952