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By A. C. Burr

This progress report covers the period from January 1949 to the end of the fiscal year, June 30, 1950. Three runs were successfully completed, and one run was terminated as the result of failure of a cast reaction tube. Including the abbreviated run, the gasifier was operated for 1,915 hours, during which some 428 tons of natural and steam- dried lignite was partly gasified In producing 20 million cubic feet of gas. Gas-production rates varied from 7.8 to 16.4 thousand cubic feet per hour, the latter being the highest production rate yet reached; hydrogen-carbon monoxide ratios of the product gas varied from 1.85, the lowest ratio yet produced, to 6.5; and heat-transfer rates through the heated wall of the outer tube varied from 2,100 to 4,400 B.t.u. per square foot an hour. The general objective of the project is to establish the technology and economy of the gasification of lignite in an externally heated, metal, annular retort. Specific objectives include determination of the useful life of the metal retort tube, which is a continuing problem, and special objectives that were established for each run as part of the systematic investigation of the basic variables of the gasification process. For runs 10 and 11 the special objective was the influence of the lignite feed rate on gasification; for run 12, a comparison of dried and natural lignite, and the production of gas having a hydrogen-carbon monoxide ratio less than 2; and for run 13, the influence of a gradually increasing steam rate with steam admitted to either the upper or lower reaction zones. In addition, during each run the sulfur distribution and concentration in the product gas and char were investigated. Experimental results obtained using the lignite feed rate as the variable indicated that the gas yield per ton of natural lignite varied inversely with the feed rate. Comparison of the gasification of natural and steam-dried Dakota Star lignite indicated that the dried lignite was a superior gasification material because: 1. The hourly gas production was higher at normal combustion space temperatures under nearly equal experimental conditions. 2. On the moisture- and ash-free basis, a considerably higher feed rate could be maintained at a relatively high percentage of carbon gasified. 3. At nearly equal moisture- and ash-free feed rates, the specific gas yield was higher. The location of steam admission was found to be important because the gas yield per ton of natural lignite was higher when at least a portion of' the process steam was admitted to the upper reaction zone. Heat balances showed the potential heat in the gas and char to be 71.8 to 83.6 percent of the total heat input. The sulfur concentration in the product gas was low, being in the range of 35 to 140 grains per 100 cu. ft., of which 1.5 to 2.3 grains was organic sulfur. Careful measurements and inspection of the 310-alloy rolled plate tube following runs 11, 12, and 13 showed no excessive corrosion; however, some radial deformation had occurred indicating that deformation or creep might be the limiting factor in the life of the tube.

Jan 1, 1953

By John J. Henn

An evaluation is presented of the Bureau of Mines process for the recovery of metal and mineral values from municipal incinerator residues. This process employs standard mineral beneficiation techniques and is operating on a pilot-plant scale of 1,000 pounds of incinerator residue feed per hour. Products from this separation process include ferrous, aluminum, and copper-zinc scrap, and colorless and colored glass. Cost estimates were prepared for four plant sizes. The estimated capital and operating costs For the four plants follow: [ ] It is assumed that the separation plant is located adjacent to a municipal incinerator. Provision is made, however, for part of the residue feed to be delivered by truck so that one large separation plant can be used for residue from more than one incinerator.

Jan 1, 1971

By P. Kawulka

An integrated pilot plant for the development of the S-C Copper Process was constructed at Fort Saskatchewan in 1975 and operated in 1976. The pilot plant was designed to treat 9 tonnes per day of a pyritic copper concentrate. A demonstration run conducted during the last quarter of 1976 averaged 90% on-stream time, and confirmed that the process is operable as a stable and integrated unit. The paper describes the parameters and equipment developed for thermal activation of chalcopyrite copper concentrates to make them amenable for the dissolution of iron and zinc, and their subsequent separation and recovery. The resulting high-grade copper sulphide was leached with return electrolyte and oxygen to extract 98.5% of the copper into solution. The copper was electrowon at 650 amps per square metre from purified solution, to produce cathodes analyzing 0.1 ppm Se, 0.1 ppm Bi, 4 ppm Pb and 10 ppm S. The electrical conductivity was >101% lACS and the spring elongation value [ ]350 mm. Elemental sulphur and gangue are removed from leach residues to make a concentrate containing over 95% of the silver and gold and most of the unleached copper. Conventional construction materials such as stainless steel, titanium, Hastelloy, acid brick, rubber and plastics performed well. The containment inherent in hydrometallurgy provided high standards of hygiene and safety.

Jan 1, 1978

By Philip Lindstrom

Retreat mining, using yielding steel friction props, over a seven-year period has been successful at a uranium mine operated by Hecla Mining Company in southeast Utah. The support system allow good roof control, maximum profit, complete extraction, and good ventilation. Unusual subsidence observations were made in that some of the surface was raised rather than lowered, Longwall mining, commonly practiced in European coal mines, has a potential of broader application because of mechanization possibilities and better roof control and ventilation at greater depths.

Jan 1, 1964

By C. Q. Cupps

n view of increased interest in secondary recovery of oil in the Cut Bank field, Montana, a review has been made of unpublished data obtained during a 1943-44 study of reservoir oil characteristics in this field. Considerable uncertainty was attached to interpretations of subsurface oil sample analyses from six Cut Bank zone wells, one Lander sand well, and one Moulton sand well, because of adverse sampling conditions and wide range in the data. Much of this uncertainty has been removed by this review which has shown two of the Cut Bank zone samples and the Moulton sand sample to be representative of the reservoir oils. Estimates of original reservoir oil characteristics derived from differential-liberation analyses of these samples show that the oil in the Cut Bank zone was initially saturated at the gas-oil contact pres-sure, 750 psia, and the oil in the Moulton sand was undersaturated with a saturation pressure of only 380 psia. The rest of the samples were indicated to be nonrepresentative of the reservoir oils because of a disproportional vaporization of heavier components of the solution gas. The vaporization of these components is believed to be a cumulative effect of contact of the oil with bypassing, light-gravity gas which had been liberated at higher pressures from solution in oil farther back in the formation, or which had come from the gas cap, rather than from the singular effect of gas evolution caused by excessively low bottom-hole pressures. Change of oil composition caused by the latter was found to conform closely to that occurring during a differential liberation of gas in the laboratory.

Jan 1, 1967

By D. Marino

Over the last 20 years, the manufacturing sector of our country has been called upon to comply with ever core stringent environmental standards. The primary metals sector was particularly hard hit early on, to develop the technology, acquire the equipment, and implement the programs to eliminate or reduce the by-products of metal making. To this end, through a combination of technological innovation and extensive capital expenditures, the metals industry has met, and in many cases, exceeded the minimum standards. It is to this escalating cost - liability exposure issue - that Dereco has addressed itself. As we move into the decade of the 90's, the challenge facing the metals industry concerning the environment will be even more difficult than the previous decade. To focus in on one major aspect of legislated environmental regulations, the issue we will address today is; now that the by-products of metal production have been identified, accounted for and collected, how are they to be disposed of? During the course of this presentation, actual data will be presented from our 4 1/4 year on-site experience at J & L Specialty Products

Jan 1, 1992

By Carl Zapffe

THE object of the Bradley process is to free manganese oxide from its associated gangue and separate the contained iron oxide by dissolving the manganese and precipitating it from the solution. 'The fundamental features of the process are : making. both 1 a manganese ore and an iron ore; effecting a separation of manganese .and. iron by means of selective roasting; leaching- the manganese from the roasted ore by using ' ammonium sulfate; precipitating the manganese by using the ammonia gas generated during leaching; fixing the precipitate by oxidizing with air; breaking down and reforming the ammonium sulfate, so that daily very little additional ammonium sulfate beyond that originally charged into the system is required; washing the manganese precipitate and the iron-silica residue and evaporating the liquor to conserve the dissolved salts in the moistures of these two products and 'to reduce the sulfur content,; drying the precipitates; magnetic wet-concentration of the iron-silica residue; sinteriny the manganese-and .the' iron-concentrates.

Jan 1, 1929

By M. Frenzel, K. Bachmann, M. Rudolph, R. Tolosana-Delgado, E. Schach, M. Buchmann, L. Pereiraa, K. G. van den Boogaart, N. Kupka

Geometallurgy - the science of predicting the behaviour of ores along the value chain based on their geological and mineralogical characteristics - has barely moved beyond process minerology studies. These studies typically link process behaviour to the mineralogical and microstructural characteristics of pristine or processed ores in a qualitative or semi-quantitative manner. Eventually, a trial-and-error optimisation of the operation is achieved. However, to deliver on its promise, geometallurgy should progress beyond this current approach to a fully quantitative understanding of process behaviour, including the various uncertainties involved, namely predictive geometallurgy. One of the barriers currently hindering this development is the neglect of most ore characterisation data obtained in geometallurgical studies. This is mostly due to the large extent of this information exceeding the capacity of conventional software. To address this challenge, we developed a data mining platform consisting of an SQL database, an R front-end in-house package, and back-ends to interpret data from several analytical instruments. This platform enables the use of the statistical and data mining power of the R open-source environment for any geometallurgical study. Potential applications range from ore characterisation to process understanding and forecasting, and from geostatistical prediction to operational control and optimisation. The scripting abilities of R allow for the: 1) processing of many streams in loops, thus freeing the user from repeating tedious click-and-drop tasks; 2) computation of virtually any derivate or aggregate quantity from the data; 3) distribution of the work among several processor clusters; and 4) keeping of a log file for the calculations done. This contribution presents the building blocks of this platform, and illustrates with several examples its potential to enable predictive geometallurgy. Keywords: Data mining, entropy, kernel methods, LASSO regression, predictive geometallurgy

Jan 1, 2020

By Oliver Q. Leone

Three electrorefining cells were designed to investigate various factors associated with the electrorefining of reject - grade titanium sponge . Operation of the cells provided information on cell design as well as on how design and operating variables affected the quality of the titanium product . A sodium chloride - titanium chloride electrolyte was used , and the electrolyte chambers had capacities ranging from 400 to 3,500 pounds of molten salt . Major factors investigated were electrolyte composition , temperature and useful life , effect of various cathode shapes and materials of construction , methods for removing cathode deposits , effect of current density and cell potential , and the mechanics of deposit growth and crystal morphology . One of the cells was in intermittent operation over a 4 - year period and produced 2 tons of refined titanium . A product with a hardness of 80 or less Bhn (Brinell hardness number ) was consistently and easily obtained . Some metal with a hardness of less than 60 Bhn was produced . In one of the cells in which the electrolyte was held at operating temperature with an internal heater an ac input of 25 kw maintained 3,500 pounds of electrolyte at 850 ° C , but with an external heater 35 kw was required to maintain 400 pounds at 850° C.

Jan 1, 1964

The United States Bureau of Mines is establishing a computerized mineral inventory system to help the Federal Government appraise its mineral position and prepare programs insuring against critical shortages of materials. This system, called the Minerals Availability System (MAS), is a component of the Bureau's minerals intelligence function designed to conduct and maintain an inventory of minerals important to the Nation. The MAS defines the physical and commercial availability of the mineral resources. Known resources are evaluated and classified by deposit for entry into a computer storage and retrieval system. An integral concern of these evaluations is the cost of mining and beneficiating the ore contained in specific deposits. To meet this concern, a cost handbook was developed as an aid to preparing feasibility-type estimates for capital and operating costs of mining and primary beneficiation of various types of mineral occurrences. Cost data, obtained from U.S. and Canadian companies, were used as the basis of this handbook. The handbook presents cost curves and equations for each component of the mining and beneficiation process. Factors for each cost component are also given, thereby allowing the updating of cost for time, geographic location, labor rates, and mining and milling conditions. Included in the latter conditions are items such as the length of haul, need for rock bolts, and a rock work index for ores and rocks of various hardnesses. 1.2. USE OF THE HANDBOOK Using the handbook a feasibility-type estimate falling within 25% of expected actual cost is obtainable by summarizing cost components. This handbook should not be used to determine the cost of any single component of a mining or beneficiation system, as any single component may not fall within the 257 limit. It must be understood that anyone who uses the handbook must have a comprehensive knowledge of mining and processing technology and cost estimating procedures. The handbook was intended to be used internally by the Minerals Availability System. Because

Jan 1, 2012

By B. W. Gandrud

[The Bureau of Mines is conducting an extensive investigation of coal preparation in the Alabama coal fields in cooperation with the University of Alabama and coal-mine operators. In this investigation the drainage characteristics of typical coals from the Warrior and Cahaba n fields were studied. Tire main purposes of this study has been to evaluate no nearly as possible relative influences of certain factors on rate of drainage and to determine whether the drainage characteristics of coals from different beds or from different mines on the soma bed differ materially. A further objective was the development of a laboratory drainage test that would predict approximately the rate at which any coal will drain after having been loaded into a railroad car in a saturated condition. The study has been confined to samples of slack coals - that is, coals from which none of the fine sizes have been removed. The samples ranged in upper size limits from 7/16 inch to 3 inches. It did not seem necessary to study nut and egg sizes, that is, sizes from which the fine coal has been removed by screening, as these lose water so rapidly by natural drainage that they present no serious problem in dewatering after treatment in a washer. The significance of drainage characteristics of Alabama coals is apparent in view of the fact that not less than 70 percent of Alabama?s total coal product is subjected to wet washing before being materials.]

Jan 1, 1941

By Josh Swank

Albert Einstein once said, ?the important thing is not to stop questioning.? In the mining industry, a lack of inquisitiveness may lead to a blissful ignorance but it certainly will not increase efficiencies. While one may claim necessity is the mother of invention, questioning and analyzing how methods and systems can be improved is the catalyst to discovering necessities. Understandably, when working in the middle of Canada?s oil sands, where trucks operate around the clock every day of the year, it is nearly impossible to pull the nose from the grindstone long enough to provide thorough analysis. But, fortunately, some manufacturers/inventors have assisted by examining the process and the ensuing headaches within this application.

Jan 1, 2013

By Lixue Wen, Jun Xiao, Dongping Shi, Yan Xue, Jinmiao Wang

Mine ventilation energy consumption is one of the main sources of energy consumption in mining production, accounting for about one-third to one-half of the total energy consumption. Therefore, reducing the energy consumption of the mine ventilation system is crucial for mining production. With the premise of meeting the airflow requirements of the underground work areas and achieving sustainable development of mining production, this paper establishes a nonlinear optimization mathematical model for the mine ventilation network with the objective of minimizing the total power. Regarding the model, optimization of the decision variables was carried out using the method of minimum spanning tree. The constraints for air flow balance, wind pressure balance, and fan operating conditions were optimized using the exterior penalty function method, thereby transforming the model into a nonlinear unconstrained model. Based on this model, a modified sooty tern optimization algorithm (mSTOA) was proposed to achieve optimization. Improved the sooty tern optimization algorithm (STOA) by using the uniform reverse strategy, fitness value-distance balance selection strategy, and mutation strategy. The STOA, mSTOA, and three other classical optimization algorithms were applied to the optimization of a ventilation system of an actual mine. The experimental results show that after using mSTOA to optimize the ventilation network airflow distribution in the mine, the total energy consumption can be reduced by about 35.06% while meeting the constraints and demands of the ventilation network regulation and usage. This is of great value to mine roadway operation environment safety and clean production.

Dec 20, 2023

By D. K. Marjaniemi

The U.S. Bureau of Mines inventoried and characterized mineral sites and production plants within 200 km of the border in both the U.S. and Mexico. Sources of information included the USBM Minerals Availability System, the USBM Automated Mineral Information System, the USGS Mineral Resources Data System, the Mine Safety and Health Administration Address/Employment File, and the literature. Three hundred seventy-eight major construction material and industrial mineral properties were identified and characterized in the U.S. and Mexican parts of the Borderlands. Sixty-six major metallic mineral properties were identified and characterized in the Mexican part of the Borderlands.

Jan 1, 1996

By B. W. Gandrud

[The Bureau of Mines is conducting an extensive investigation of coal preparation in the Alabama coal fields in cooperation with the University of Alabama coal-mine operators. In this investigation the drainage characteristics of typical coals from the Warrior and Cahaba fields were studied]

Jan 1, 1941

By Shawn McWilliams, Aini Sun, Mike Lichte, Greg Colzani

The Allegheny County Sanitary Authority (ALCOSAN) adopted its Clean Water Plan (CWP) in May 2020, as part of a federal consent decree to comply with the USEPA’s Combined Sewer Overflow (CSO) Control Policy. Planned improvements include constructing a new regional storage/conveyance tunnel system, promoting green infrastructure/ source control, and expanding the treatment plant. Preliminary planning for the tunnel system was completed in October 2020. The Ohio River Tunnel (ORT) project is the first of three tunnel projects that make up the regional tunnel system. The ORT project began final design in 2021. This paper discusses the advancements made to the ORT preliminary planning concepts considering property availability, alignment optimization, tunnel boring machine evaluation, contract packaging and delivery schedules.

Jun 13, 2023

By David White

This paper is the result of a comparative study of ultimate coal analyses made and published by the United States Geological Survey. This study, at first casually undertaken to devise an acceptable classification of coals based on chemical analyses, was continued in connection with a microscopic examination of a number of the coals. The initial comparisons, made from a relatively small number of analyses, not only confirmed a previous conviction that the elimination of oxygen incident to the development of a coal is economically far more important than has been generally suspected, but also showed that oxygen is very nearly as harmful as ash in coal. The immediate purposes of the present study were: (a) To determine more definitely, from a comparative examination of a large number of ultimate analyses, the relative importance of oxygen as an impurity in various coals; (b) to illustrate the transition between various grades of coal of similar origin-transition mainly due to progressive devolatilization, brought about more or less directly by dynamic influences; (c) to ascertain the relative proportions of oxygen, hydrogen, and carbon in coking coals, especially with reference to a theory tentatively framed to explain the coking quality; and (d) to forecast the probabilities of successfully treating a large number of coals so as to render them amenable, in a softened condition, to satisfactory study under the microscope.

Jan 1, 1911

By Q. Han

A modified cast-on method has been developed to reinforce aluminum castings with steel insert. Defect-free bond between the steel insert and the aluminum casting has been consistently obtained. Data obtained from a push-out experiment indicated that the bond strength was much higher than that obtained using the Al-Fin approach. This paper introduces this modified method in four sections: the coating of the steel pins, the cast-in method, microstructure characterization, and the bond strength. The section on the coating of the steel pins contains coating material selection, electro-plating technique for plating Cu and Ni on steel, and diffusion bonding of the coatings to the steel. The section on cast-in method deals with factors that affecting the quality of the metallurgical bond between the coated steel and the aluminum castings. The results of microstructure characteristics of the bonding are presented in the microstructure characterization section. A push-out experiment and the results obtained using this method is described in the section of bond strength/mechanical property.

Jan 1, 2015

By David White

This paper is the result of a comparative study of ultimate coal analyses made and published by the United States Geological Survey. This study, at first casually undertaken to devise an acceptable classification of coals based on chemical analyses, was continued in connection with a microscopic examination of a number of the coals. The initial comparisons, made from a relatively small number of analyses, not only confirmed a previous conviction that the elimina- tion of oxygen incident to the development of a coal is economically far more important than has been generally suspected, but also showed that oxygen is very nearly as harmful as ash in coal. The immediate purposes of the present study were: (a) To deter- mine more definitely, from a comparative examination of a large number of ultimate analyses, the relative importance of oxygen as an impurity in various coals; (b) to illustrate the transition between various grades of coal of similar origin-transition mainly due to progressive devolatilization, brought about more or less directly by dynamic influences; (c) to ascertain the relative proportions of oxygen, hydrogen, and carbon in coking coals, especially with refer- ence to a theory tentatively framed to explain the coking quality; and (d) to forecast the probabilities of successfully treating a large number of coals so as to render them amenable, in a softened condition, to satisfactory study under the microscope. Although the hypothesis as to coking quality finds but partial support in the chemical analyses, its consideration has led to a method of predicting from an analysis with a fair degree of certainty whether any given coal will coke by the ordinary process. The unbroken transition between coals originally similar but now classed in widely different groups, whether of the same age or of different ages, as a result of dynamochemical action, appears demonstrated by the analyses as well as by field observation. This subject will not be

Jan 1, 1911

By J. D. Price, W. M. Bertholf

One of the chief difficulties with which the operator of a coal washing plant has been forced to contend is the handling of the very fine coal. First he has the problem of separating the fine coal from washery water. This is usually accomplished by the use of settling cones or Dorr thickeners: in either event the separated fine coal contains a high amount (40 to 80 pct) of water and, somewhat loosely, dependent upon the size of the coal particles present, may be known as sludge or slurry. His second problem is the satisfactory further dewatering of such separated sludge and/or slurry.

Jan 1, 1949