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By C. F., Christopher

The purpose of any steel-making process is to convert the two raw materials iron and scrap into steel. The chemical analysis of the steel is set within certain limits which involve the physical proper- ties desired by the consumer. In addition to tensile properties a large number of other properties are at the present time desired, such as impact resistance, grain size regulation, specific degrees of hardenability, resistance to creep at high temperatures, resistance to expansion on heat treatment, the ability of the product to undergo extreme amounts of cold deformation without failure, and many other properties which are not directly related to the specified chemical analysis. Variations in many of the properties of plain-carbon steels are due to elements and compounds not included in the ordinary "five element"§ composition. Such variations result primarily from variations in oxidation of the metal in the furnace and from the deoxidation method employed. The steel-making problem therefore resolves itself into two distinct sections: (I) the elimination of certain elements from the charge (the iron and scrap entering the furnace) and the addition of materials to meet the chemical specifications for the heat; (2) the manipulation of the slag and metal and the process of deoxidation to give certain desired properties in the steel entirely apart from the chemical analysis specified. Each of 'these two ends must be attained

Jan 1, 1957

By L Dzinza, K C. Corin, M Tadie

The recycling of process water comes with increased electrolyte concentrations that affect water quality, which may in turn affect the flotation performance of valuable minerals (Hirajima et al, 2016). Electrolytes such as Ca2+, SO4 2- , Mg2+ and S2O3 2- have been surmised to have an impact on the action of flotation reagents such as collectors (Ikumapayi et al, 2012). Xanthate collectors are known to play a significant role in imparting hydrophobicity on mineral surfaces to enhance their flotation. The interaction between minerals and xanthates is well known to be electrochemical in nature. Such redox processes may be elucidated by electrochemical techniques. Since the mechanisms involving the interactions between electrolytes in process water with sulfide minerals and the subsequent adsorption kinetics of collectors are not well understood, this study therefore aims to provide fundamental knowledge to unpack the mechanisms involved when electrolytes interact with Platinum Group Minerals (PGMs) and how these interactions may affect xanthate adsorption. The interaction of sodium iso-butyl xanthate (SIBX) in the presence of electrolytes at increasing ionic strength was investigated by rest potential measurements, to explain the impact of electrolytes on the adsorption of SIBX on PGMs in the flotation process. Rest potential measurements for PdTe2 and PdS were conducted in an air saturated 0.05 M di-sodium tetraborate decahydrate solution, in the absence and presence of SIBX and electrolytes. It was found that the existence of sulfide and telluride on palladium affects the mechanisms in which electrolytes interact with Pd mineral surfaces. An increase in the ionic strength of Na2S2O3, CaCl2 and MgCl2, increased the interaction between the salts and PdS, thus decreasing the extent to which SIBX interacted with PdS. An increase in ionic strength for Na2S2O3 increased the interaction between Na2S2O3 and PdTe2 and therefore decreased the extent to which SIBX interacted with PdTe2. Other salts investigated in this study increased the rate of oxidation of PdTe2 with an increase in ionic strength thereby enhancing the interaction of SIBX and PdTe2. This study has shown that mineral type, electrolyte type and concentration all have an impact on the mechanisms that result in the adsorption of SIBX on PGMs.

Aug 24, 2022

By G. Djambazov, D. Shevchenko, D. Burnard, V. Bojarevics, K. A. Pericleous, W. Griffiths

Contactless ultrasound treatment can be useful for high-temperature or reactive alloys in the liquid state, where contact with an immersed vibrating probe is undesirable. The alternating component of the Lorentz force can generate sound pressure levels leading to cavitation of gas bubbles in the melt, through acoustic resonance. Resonance is a function of the speed of sound in the liquid, the shape of the volume containing it and surrounding boundary conditions. Induction forces applied to a crucible lead to bulk stirring and in general deform the free surface, whose precise shape may influence the resonance conditions. This effect is investigated here b ymulti-physics computer modelling. Calculated results for aluminium melts are compared with experimental data and conclusions are drawn as to the sensitivity to process parameters and the reliability of this type of ultrasound metal processing.

Mar 1, 2017

By Willie M. NeSmith, W. Morgan NeSmith, Alan Roach

"In 2013, Augered Cast-in-Place (ACIP) piles are a mature foundation technology throughout the United States. General guidelines for the design and construction of ACIP piles are available along with numerous references for design in specific North American geologies. In fact, the current generation of contractors and geotechnical practitioners might view ACIP piles as just another deep foundation option to be considered, along with driven piles, drilled shafts and others. This acceptance has developed, however, over a 60-plus year period.The term, Augered Pressure-Grouted (APG) pile is often used when referring to ACIP piles because the piles emerged out of construction processes at the Intrusion-Prepakt firm in the late 1940s. The company’s specialty was pressure grouting and preplaced aggregate concrete. The grouting was typically accomplished by driving a pipe to a target level and then injecting grout under pressure. In some soil conditions, it was necessary to use an auger to reach the desired grouting depth. In these circumstances, the grout pipe was driven beside the auger and grout was pumped as the auger was withdrawn. The grout pipe was then withdrawn as well. This was the genesis of the APG, or ACIP pile, and many piles were installed using this technique. The patent application, “Method for Forming Piles” was filed by Raymond Patterson of Intrusion-Prepakt in 1951, and the patent was granted in 1956. The process was eventually modified when a suitable hollow-stem auger was developed. Licenses were granted to the Lee Turzillo Contracting Company and Berkel & Company Contractors, Inc. in the late 1950s. Each of the three companies Patent, LicensesThe patent application, “Method for Forming Piles” was filed by Raymond Patterson of Intrusion-Prepakt in 1951, and the patent was granted in 1956. The process was eventually modified when a suitable hollow-stem auger was developed. Licenses were granted to the Lee Turzillo Contracting Company and Berkel & Company Contractors, Inc. in the late 1950s. Each of the three companies coined their own terms for the piling process: “Pakt-In-Place” for Intrusion-Prepakt, “Auger Pressure-Grouted” for Berkel and “Augercast” for Turzillo. Over time, “Augercast” was frequently used as a generic term for the system. The installation of these piles was, and still is, a highly nuanced process; “contractor dependent” is a term often seen today. Intrusion-Prepakt, Berkel and Turzillo all had personnel who were part of the original group that developed the system and who appreciated the craftsmanship involved in forming sound piles."

Jan 1, 2013

By M. P. Bohrer

A closed-loop hydrometallurgical process has been developed for treatment of smelter flue dust generated by copper recycling. The process is a semi-continuous operation in which zinc, iron, and copper are first extracted from the dust with a sulfuric acid solution. The lead and precious metals, initially present in the dust, remain as solids and can be recycled to the copper smelting furnace. Cementation with iron and zinc metal purifies the zinc and iron-rich liquid stream prior to spray drying. The spray-dried product, consisting of a mixture of zinc sulfate monohydrate and iron sulfate monohydrate, is a desirable micronutrient additive for use in animal feeds. Treatment of the smelter flue dust in this manner will generate a positive return on investment, as well as mitigate a potential environmental liability.

Jan 1, 1992

By Ludwig Schmidt

Steel tanks often corrode rapidly in oil fields where the gas produced with crude petroleum contains an appreciable quantity of hydrogen sulphide. In many instances working tanks have been discarded after only six months of service because of failure induced by corrosion. Aluminum has been used for some time in the fabrication of certain equipment incidental to the handling of oils containing hydrogen sulphide gas in solution, and has exhibited no serious corrosive action. These uses indicated that aluminum tanks might be equally effective in counteracting hydrogen sulphide corrosion. Consequently, in the spring of 1928, an all-aluminum stock tank of 500 barrels capacity and a "composite" tank of equal capacity, having a steel bottom and bottom ring and an aluminum top and top ring, were placed in service on the State-Lassiter lease of the Gulf Production Co. in Crane County, Tex. These tanks were under observation for one year, the test being sponsored by the Gulf Production Co., the Aluminum Co. of America, rind the Parkersburg Ric and Real Co. The results of this preliminary test sustained the belief that aluminum is highly resistant to hydrogen sulphide gas and likewise indicated the type or grade of aluminum which could be most economically used for lease tankage. However, in this preliminary test the Wake were not subjected to contact with the large quantities of highly concentrated brines such as often are associated and produced with crude oil. Therefore, it was suggested by representatives of .the Aluminum Co. that additional tests be made to include production conditions in which large quantities of brine would be handled, for past experience had shown that aluminum often is susceptible to the corrosive action of brines.

Jan 1, 1931

By Ludwig Schmidt

[Steel tanks often corrode rapidly in oil fields where the gas produced with crude petroleum contains an appreciable quantity of hydrogen sulphide. In many instances working tanks have been discarded after only six months of service because of failure induced by corrosion. Aluminum has been used for some time in the fabrication of certain equipment incidental to the handling of oils containing hydrogen sulphide L; as in solution, and has exhibited no serious corrosive action. These uses indicated that aluminum tanks might be equally effective in counteracting hydrogen sulphide corrosion. Consequently, in the spring of 1928, an all-aluminum stock tank of 500 carrels capacity and a "composite" tank of equal capacity, having a steel bottom and bottom ring and an aluminum top and top ring, were placed in service on the State-Lassiter lease of the Gulf Production Co. in Crane County, Tex. These tanks were under observation for one year, the test being sponsored by the Gulf Production Co., the Aluminum Co. of America, and the Parkersburg Rig and Real Co. The results of this preliminary test sustained the belief that aluminum is highly resistant to hydrogen sulphide gas and likewise indicated the type or grade of aluminum which could be most economically used for lease tankage. However, in this preliminary test the tanks were not subjected to contact with the large quantities of highly concentrated brines such as often are associated and produced with crude oil. Therefore, it was suggested by representatives of the Aluminum Co. that additional tests be made to include production conditions in which large quantities of brine would be handled, for pact experience had known that aluminum often is susceptible to the corrosive action of brines.]

Jan 1, 1931

By M. Pearson, W. Bristowe, A. Hanson

"There's no such thing as quality assurance; only quality control ... by inspection. "(1) A common misunderstanding in the procurement and construction of custom designed, fabricated pressure vessels and piping systems is that quality assurance can be achieved by simply referencing codes, standards, ISO 9002, QMS or other such programs in the contract documents. In the authors' experience, nothing could be further from the truth, not detrimental to the performance of the equipment than the exclusion of inspection activities and reliance upon warranties and "fit-for-purpose" clauses. Likewise, the expectation that fabricators, suppliers, or third party inspectors can provide such assurances is also unrealistic where they have limited knowledge of the process, material selection criteria, or limited technical resources. The development and successful execution of a quality assurance program is a collaborative effort by engineers, designers, material suppliers, equipment fabricators, and field inspectors with the full understanding and support of the end user.This paper presents an outline of the quality control activities undertaken by the authors for several recently completed and on-going hydrometallurgical projects. The activities include: prequalification of fabricators and sub-vendors, shop audits, material validation testing, material source control and verification, positive material identification of weld metal overlay, specialised welding inspection, contamination control for titanium and titanium-clad fabrication, eddy current and mass spectrometer (helium) leak testing of shell-and-tube heat exchangers, hot cycle testing of titanium clad equipment, tolerance verification for refractory lined equipment, final inspection and cleaning.

Jan 1, 2004

By H. S. Martin

This paper, describing the concentrating practices at the plants of the Utah Copper Co., is one of a series being prepared by the United States Bureau of Mines in which the data are given in as nearly uniform c manner as possible. The Magna mill is 19 miles west of Salt Lake City on the routes of the Lincoln and Victory highways, and the Arthur plant is 1 mile west of the Magna mill. Both are on the main road west of the town of Magna and east of the town of Garfield.

Jan 1, 1931

By Francis Gray

Mr. F. W. Gray: It is not my intention to read my paper as it is too long, so I will touch only on the high lights. The Sydney field is the most favourable example of undersea coal mining that exists, and I have not been able to find anything like it elsewhere. The nearest approach to it is a field in England where the Whitehaven collieries are operating, but it has a lot of faults. The net result of these faults so far met with in the seaward advance of the workings has been to increase, by something over 100 feet, the gain in depth of cover, in a distance of approximately three and three-quarter miles. In the Sydney field there are no faults of any consequence. On the east side, the English measures rise. In Australia the sea bottom fell and the cover became too light. On Vancouver Island the coal ran out, and in Japan the seams are steep and contorted. The Chilian fields resemble our own to some extent. An inundation of two collieries took place there some time ago, due, it is said, to the rise workings being allowed to approach the sea bottom too closely in the vicinity of a fault. The Cape Breton undersea field has been proved over a frontage of about thirty miles and has been attacked and penetrated for a considerable distance along that front. We have passed the prospecting stage and now generally use developed land areas as points of attack to win the undersea coal. Of our mining under the sea, it can be said that, with the exception of No. 1-B and Princess colliery, Sydney Mines, no real attempt has been made to win the undersea coal.

Jan 1, 1927

By M. J. Howes

The high degree of mechanisation, which is mainly diesel-powered, has a significant effect on heat loads; heat output from this source often exceeds the heat flow from the surrounding rock. The extensive use of diesel-powered equipment also influences ventilation rates and minimum values are necessary to ensure that emissions of diesel exhaust are adequately diluted. Many Australian mines are in subtropical or tropical areas with high ambient wet- and dry-bulb temperatures on surface. This, coupled with the large amount of heat from mechanisation, usually means that refrigeration is required at much shallower depths. A secondary problem is associated with the definition of acceptable thermal environment conditions, which are sometimes based on the assumption of no air movement. This gives rise to very stringent thermal environment acceptance criteria, which, in some areas, would prohibit work on surface, let alone underground

Jun 12, 1905

By M. J. Kirwan

[There have been large increases in the oil production and casing-head gas production of certain wells on the Quinn dome (northern part of the Lyons-Quinn field of Oklahoma) caused by large volumes of gas under high pressure entering Vie productive oil sand, The oil production of sore of the leases in this part of the field temporarily increased over 100 per cent within a few days after gas entered the oil sand among the leases that had the greatest increases in oil production wore those on which no gas wells were drilled but which were located up-elope on the structure in reference to gas wells on adjoining properties. It is conservatively estimated that 1,444,000,000, cubic feet of gas entered the productive oil sand and, up to January 1, 1924, caused an increase of about 950,000 barrels of oil from this sand. The casing-held gas volumes of a number of wells producing between 25,000 and 75,000 cubic feet of gas per day increased to several hundred thousand cubic feet and a few walls increased to nearly two million cubic feet per day after extraneous gas entered the oil sand from which the wells were producing.]

Jan 1, 1924

By K. L. Paciorek

The aim of the present study was to determine the thermal oxidative behavior of materials used in coal mines, with emphasis on the type and relative concentration of the products, in particular the toxic species formed. To supplement this work and to gain understanding as to the type of products possibly formed and also to assess the limitations and advantages of the various analytical methods used a literature survey of the past investigations performed on the compositions of direct interest to the subject program was conducted. The compositions thus covered were cellulose, polyvinyl chloride, neoprene, urethanes, polyamides, polyesters, polyethylene, epoxy, phenoxy, urea-formaldehyde and melamine formaldehyde resins. The results of this review are compiled in the Appendix. The experimental work consisted of thermal oxidative degradation of 36 materials and 4 composites using a stagnation burner apparatus developed in these laboratories which affords a dynamic system approximating somewhat the conditions encountered in underground coal mines. This technique as employed during this program gave only the relative product concentration at specific periods of the decomposition process, The advantage of this approach is that in this manner screening of materials can be accomplished in conjunction with some assessment of the decomposition rate as influenced by temperature and material composition. Limited static tests were performed using a sealed tube method. The materials studied were grouped according to their compositions. The following were the main groups: (a) polyvinyl chloride-containing materials, (b) neoprene compositions, (c) rigid foams (urethanes, isocyanates), (d) miscellaneous materials (including jute, fiberglass, polyethylene and some articles of unknown composition), (e) coal and fluids (phosphate esters, organic esters, oil-water emulsions), and finally (J) composites. The latter comprised a mixture of a phosphate ester fluid with (a) coal, (b) a representative polyvinyl chloride sample, and (c) a neoprene type composition.

Jan 1, 1972

By J. T. Dunham

Zirconium has possible use in industry where severe corrosion conditions are encountered because it resists attack from a variety of corrosive environments. However, very little experimental testing has been done to evaluate the corrosion behavior of zirconium when simultaneously subjected to high tensile stresses and exposed to corrosive environments. This investigation was initiated for an evaluation test, but was limited to environments consisting of ferric chloride solutions which were known to attack zirconium and were shown to promote stress-corrosion cracking in preliminary tests. Tests for cracking susceptibility were conducted by the Bureau of Mines to show the effect of stress, solution concentration, air aeration of solution, and the method of mechanical processing. Tensile stress was applied to the specimens by a constant-load method which proved more reliable than a constant-strain method.

Jan 1, 1961

By A. U. Miller

Protection against fire is a greater problem at a coal mine, than at an ordinary industrial plant. Generally mines are located in isolated districts and do not have the protection of city fire departments; consequently fire fighting aquipment must be installed by the mining company. Fire protection around a mine is just as essential as it is in the city.. and undoubtedly is more important if the fire should be underground where many lives would be endangered and all means of escape cut off. A surface fire can generally be attacked from any angle, but an underground fire can be attacked only as conditions will permit.. U. S. Bureau of Mines engineers have investigated many serious mine fires that undoubtedly could have been extinguished in incipiency if a fire extinguisher or fire hose and water had been readily available. In past years very little attention was given..to fire fighting equipment and organization around mines, but in recent years three gen a derde hange of opinion among many of those engaged in mining, and nearly all up-to-date mining companies now have some kind of fire protection about their mine Probably the first company in Illinois to install regular fire fighting equipment and effect a fire fighting organization at its mines, was the Madison Coal Corporation, which operates several mines in Illinois. The main office of this company is in Chicago and the general field office is at Glen Carbon, Ill.

Jul 1, 1930

By G. E. McElroy, D. Harrington

In connection with the cooperative metal-mine dust and ventilation investigations of the U. S. Bureau of Mines and the U. S. Public Health Service , some underground data have been obtained with intent to ascertain the adaptability of the katathermometer for determining the comfort of working places in mines . This preliminary study indicates that the instrument will probably be useful for making routine determinations of comfort conditions in our mines , and that it may also prove an important accessory for investigative work on problems in ventilation and kindred subjects ; in both coal and metal mines , although the instrument should probably be altered somewhat for maximum utility under the varied conditions in the mines of the United States . The katathermometer is an instrument contrived by Dr. Leonard Hill , an eminent English physiologist , and its various features have been fully described by him in his book entitled " The Science of Ventilation and Open Air Treatment . " He made exhaustive experiments and concluded that the rate of cooling of the human body was the controlling factor in determining comfort or discomfort , and then set out to make an instrument that would measure this rate of cooling . The resulting instrument the katathermometer measures its own rate of cooling when its temperature approximates that of the human body and thus serves as an index of the rate of cooling of the body itself . - The instrument consists of an alcohol thermometer having a cylindrical bulb 1 inches long and 3/4 inches in diameter, and a stem about 8 inches long graduated from 95 to 100° F. This temperature range gives a mean temperature of 97.5° F. ( 36.5° C. ) , which is approximately that of the clothed body surface . The stem terminates in a small reservoir which serves the double purpose of acting as a safety overflow in case of overheating the bulb , and of insuring a regular rate of cooling by the time the meniscus has fallen to the 1000 point .

May 1, 1922

By George H. Holmes

This report describes the results of a reconnaissance survey of areas in California and Nevada considered favorable to beryllium mineralization. Pegmatite dikes, veins, intrusive sills, contact. metamorphic, and disseminated deposits as well as tactite deposits in the former major tungsten-producing districts were investigated. A general geographic pattern of beryllium mineralization was found to be concentrated along a wide belt in eastern Nevada extending from the Ruby Mountains, Elko County, south through the Fish Creek Range, Eureka County, the Snake Range, White Pine County to the Virgin Mountains in Clark County, Nev., and Mohave County, Ariz. Sporadic occurrences of beryllium are in central and southern Nevada, and in the pegmatite dikes of San Bernardino, Riverside, and San Diego Counties, Calif., and the granite masses of the southern Inyo Mountains, Inyo County, Calif. Principal company activities are centered in the Snake Range, Fish Creek Range, and the Virgin Mountains, Nev., and the Inyo Mountains, Calif. Other areas in California and Nevada have been superficially explored with results indicating either limited or widespread, but submarginal, mineralization. Although beryllium was found to occur, to some extent, in many of the deposits, mining has been hindered by the lack of a market for beryllium ores and concentrates other than standard-grade beryl and also by the erratic pattern of mineralization and the high exploration and beneficiation costs required to produce a marketable product.

Jan 1, 1963

By AIME AIME

Gentlemen, we have ten questions on our list and a number of us here probably have other questions to ask. Therefore, we arc going to allocate the time to these different questions so that we will try to be finished by 4:30; from then until 5 o'clock, if any of you have any questions on subjects not related, you will be free to ask them. Mr. Morton and I have changed the order of the questions. Instead of what is now first, we have put No. 3 first, progress on basic-roof construction, inasmuch as we feel that it is quite important. At this time, H. S. Robertson, of Harbison-Walker, is going to give you a short talk, with slides, on what has been done to date on this subject.

Jan 1, 1940

By G. L. Oldright

In the first Report of Investigations of the present series?(No. 4562) the usual course of progress ill reducing the minerals of low-grade ores to their valuable metallic components had been noted as advancing along two lines to concentrate a usually diminishing percentage of these minerals to a smaller bulk of richer product, and then to smelt the smaller bulk more cheaply per pound of metal produced. Fundamental properties of lead compounds made it difficult to treat much richer lead products than are treated at present in several steps of conventional lead smelting, unless ?marked modifications were made. No limits to the richness of the feed itself' were set by the ore (Scotch) hearth; on the contrary, the richer the feed, the better the results given by the hearth. The natural field of operation of the hearth, as determined by the ores available, was seen to lie in the Central United States, with their lead concentrates containing negligible quantities of precious metals and. with few ores of such metals available for use as fluxes. It was noted) however, that even in its chosen field, the Scotch hearth, or "ore" hearths developed from them, was not always used; the usual smelting practice was followed, at times, of sintering followed by blast-furnace smelting for even rich ores.

Jan 1, 1949

By J. M. Keane

SMEThis loaner is concerned with important criteria relative to the design of small flota¬tion concentrators. For the purpose of this discussion a small flotation concentrator is defined as a facility having a designed ore feed rate of 1,000 metric tons per day (MTPD), or less. The decision to design and construct a small flotation concentrator is the culmination of a series of logical steps relative to the ex¬ploitation of a potential ore body. The information required for a rational and timely decision regarding plant design and construction is usually contained in a feasibility report. The information required in a thorough feasibility report has been summarized (1) (2) as follows: Type of mine or plant and proposed daily, monthly, and yearly production of all intermediate and final products. Quantity of indicated ore reserves. Location of project illustrated by a map showing surroundings, trans-portation facilities, and existing utilities.

Jan 1, 1980