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By J. King Hoyt

IN both Sweden and England rapid progress is being made in metallurgical development, and the steel industry in both countries is distinctly on the mend. There has been some industrial trouble in Sweden in the iron mines and the wood pulp mills, but at the same time all the steel works have a sufficient stock of pig iron and ore to continue their operations for many months to come. Consequently the strike, unless long protracted, will not affect the output of steel in Sweden. Several of the steel manufacturers in Sweden, most notably Forsbacka and Sandviken, have been very suc-cessful recently in securing large orders, particularly from the continent, for ball-bearing steel, both hollow and solid. Whereas some years ago they ran into-se-rious competition with the German mills, the quality of the steel from these Swedish mills is such that they are now firmly established, and are selling some of the lead-ing manufacturers of bearings on the Continent, as well as automobile manufacturers. The secret of their success seems to lie in a better selection of ores, in more careful control of blast-fur-nace operations and better equipment. Rule of thumb in steel making is taboo, and strict reliance is placed on the laboratory. They are constantly experimenting, and metallurgists and chemists are sent to different countries for study and investigation. In their native ores they have, of course, a unique advantage in pos-sessing iron ores extraordinarily free from phosphorus. At Forsbacka, they are not content with the ordinary chemical analysis of the ingot; but also test the physical properties, as well as make metallographic investiga-tions for slag inclusions, segregations and oxides. In both England and Sweden they watch the nitrogen con-tent of the steel very carefully, a feature which does not appear in the ordinary analysis. In testing carbon, they do not use the color test, but employ an electric .induction device.

Jan 7, 1928

By W. H. Emmons

INTRODUCTION MINERAL deposits that have formed by the various geologic processes, when exposed to air and water at or near the surface of the earth, break down and form new compounds that are stable under surface conditions. Mechanical disintegration of the ores proceeds along with chemical alteration which generally is attended by oxidation, carbonation and hydration. Essentially all minerals are affected-silicates, carbonates, native metals, sulphides, etc. Where iron sulphides are present, oxidation yields sulphuric acid, and in the presence of oxygen and iron, ferric sulphate, a powerful solvent, is formed. Above the water level, in the vadose or shallow zone, both air and water are present. Below the water level air is excluded and that which is carried down with water is removed from the solution by reactions with reducing materials. Above the water level, solution is the pre-dominating process; below the water level, precipitation generally is equally important. In some deposits, particularly above the hater level, valueless materials are removed from the ore, leaving certain metals in a more highly concentrated state. This type of alteration, which has been termed negative enrichment, is common in ores of iron, aluminum, manganese and certain other metals. Some gold deposits, particularly those in which the environment is unfavorable for solution of gold, have been enriched near the surface by removal of material other than gold. Certain metals are readily dissolved in an oxidizing acid environment. These include copper, silver and, under certain conditions, gold. In the presence of iron sulphides, deposits of these metals are likely to be leached above the water level. The metals are carried downward to depths where air is excluded, and where they may be redeposited, generally below the water level. Such enrichment by addition of metals has been termed positive enrichment.

Jan 1, 1933

By Makoto Yuasa, Akira Usui, Shipboard Scientists of SIP Cruises, Atsushi Suzuki, Shingo Kato, Kyoko Yamaoka, Akira Nishimura, Kiyo Kisimoto, Katsuhiko Suzuki

"We report here on current topics of our project, based on the results of recent cruises and laboratory analysis, about the diversity of compositions and configurations of the hydrogenetic ferromanganese deposits in several Northwestern Pacific Seamounts. This recent research has discovered important aspects of these deposits regarding the mode of variation with water depth, topography and substrate geology, possible bacterial mediation, temporal variation with age in mineralogy, and major and minor element chemistry. All cruises and analysis have been supported by the facilities and staff of the Japan Agency of Marine-Earth Science and Technology (JAMSTEC), Japan Oil, Gas, and Metal resources Corporation (JOGMEC), Geological Survey of Japan, and Kochi Core Center (KCC) using a remotely operated vehicle (ROV), a monitored rock drilling system, dredges, and manned-submersibles in the NW Pacific seamounts,The results indicate that most of the rock outcrops on the slopes, shoulders, and much of flat tops are covered with maximum 10-cm thick crusts, but the thickness, metal content, and microstructural properties are not always uniform over the seamounts, but variable in space and time. The micro-stratigraphic description of whole-rock samples indicates a history of deposition and sedimentation, which control the diversity in bulk composition and abundance caused by the variable incorporation of iron-manganese precipitates into the deposits during variable environmental conditions. We conclude that hydrogenetic precipitation of iron-manganese oxide has taken place for more than 20 million years at a growth rate about 4-6 mm/my, in water depths below 1000m. The results indicate a fairly continuous and constant metal deposition since the middle Miocene age or older to the present. Our case study of geological sciences at a model seamount within the Japanese EEZ suggests that scientific knowledge is useful and essential in exploring mineral deposits, economic estimation, and designing systems, if supported by well-combined geological and oceanographic and biological research. The distribution map of ferromanganese deposits and geological map will be published soon in 2017 to be issued by the Geological Survey of Japan."

Jan 1, 2017

By LESTER W. STRAUSS

OUR early knowledge of history and geography attracted most of us to the mineral resources of South America. The romantic tales of the Spanish activities, which were curiously alluring, and Prescott's exceptional bi-Conquest histories-Mexico and Peru-no doubt fired our minds with the .then metallic wealth of the Spanish colonies. Later developments, intensified within the past eighty years, have, however, changed its fame which now rests on such metallics as copper and tin, and among the non-metallics on nitrate of soda and petroleum. South America proper, excluding Panama, is made up of thirteen countries, a coincident parity with our original thirteen States. Its area is given as 7,231,300 square miles, or slightly less than North America (8,037,000 square miles), is made up as follows:

Jan 1, 1930

By Oliver Bowles

STRIKING new developments in the field of industrial minerals include the employment of lime, salt, coal, and air for the manufacture of stockings, and the substitution of paper for granite and marble in making tombstones. Certain minerals that have heretofore been regarded as valueless except as museum or laboratory specimens, are now being applied commercially. Serpentine, in forms neither fibrous nor ornamental, massive topaz, pinite, and zoisite are examples. For certain other minerals, notably pyrophyllite, bentonite, vermiculite, and sulphur, extension of established uses into new fields has occurred. Substitution takes a toll in many industries, but producers of industrial minerals as a class have gained more than they have lost in recent years. Encouraging progress has been made in developing at long last a suitable substitute for certain of the uses of mica, the only industrial mineral on the strategic list of commodities established by the War. and Navy Munitions Board. Some of the more important developments in process, equipment, and use .that have come

Jan 1, 1940

By H. A. Doerner

PROPOSALS to use hydrocarbon or natural gases for the reduction of zinc from oxide materials may be traced back through Patent Office files to the early years of the present century. Natural gas at rates cheap enough to compete with solid fuels has been available at or near one major zinc district for more than a decade. That the seemingly meritorious and economically interesting applications of these proposals have not devel-oped into workable processes for direct production of zinc by natural gas cannot be completely ascribed to the proverbial conservatism of the zinc industry. It is possible to produce spelter commercially in normal times from zinc oxide and carbonaceous reducing agents without having a very precise understanding of the chemistry of the process. The reduc-tion by hydrocarbons is not, however, in this class, and the technical complexity of this reduction metallurgy and chemistry prohibits solution of the inherent difficulties by the "hit and miss" methods that are some-times thought to be practical. In a thermodynamic study of the chemistry of zinc smelting, Maier1 made a preliminary study of the chemistry of the use of methane for reducing zinc oxide by thermodynamic means, pointing out that the following reactions, the limits of which could be theoretically predicted, were important: ZnO + CH4 = Zn(gas) + CO + 2H2 [1] CH4 = C -I- 2H2 [2] ZnO + CO = Zn(gas) + CO2 [3] ZnO + H2 = Zn(gas) + H2O [4] Other possible reactions, not discussed in the reference quoted, are: CO2 + CH4 = 2CO + 2H2 [5] H2O + CH4 = CO + 3H2 [6]

Jan 1, 1933

By Misra V. N, Spottiswood D. J

In recent years the column flotation process has gained worldwide acceptance for processing various types of minerals under different circuit configurations. In an age when real prices of many mineral commodities are in decline and mining and labour costs are rising in real terms, it is more important than ever that concentration processes be not only efficient but also cost-effective. The column flotation process can give better metallurgical performance as well as involve lower capital and operating costs compared to conventional mechanical cells.This paper reviews the literature on columns and the effects of various column parameters on performance of the column flotation process. The history and principles of operation of the column flotation process are briefly discussed by way of introduction.

Jan 1, 1995

By Hiromichi Ohla

Precise thermal properties of molten materials are essentially required for analyzing the metal production process. These properties are also important as a clue to consider the dynamic structure of liquid materials. However, it is difficult to obtain the precise thermal diffusivity values of molten oxides at high temperature because of the experimental uncertainties arising from the bubble formation or the severe separation of radiative and conductive heat components. Recently a novel laser flash method has also developed for measuring thernnal diffusivity of molten oxides at high temperature. In this new technique, the sample is melted in a metal crucible and heated to the desired temperature. A single laser pulse is flashed on the bottom of the metal crucible and the infrared ray irradiated from the same bottom surface is measured for obtaining the temperature decay, from which the thennal diffusivity of the liquid sample can be estimated. The usefulness and validity of this new laser flash technique have been confirmed by obtaining the thermal diffusivity values of silicate melts in the wide temperature range between 773 and 1673 K.

Jan 1, 2003

By Hiromichi Ohta

Precise thermal properties of molten materials are essentially required for analyzing the metal production process. These properties are also important as a clue to consider the dynamic structure of liquid materials. However, it is difficult to obtain the precise thermal diffusivity values of molten oxides at high temperature because of the experimental uncertainties arising from the bubble formation or the severe separation of radiative and conductive heat components. Recently a novel laser flash method has also developed for measuring thermal diffusivity of molten oxides at high temperature. In this new technique, the sample is melted in a metal crucible and heated to the desired temperature. A single laser pulse is flashed on the bottom of the metal crucible and the infrared ray irradiated from the same bottom surface is measured for obtaining the temperature decay, from which the thermal diffusivity of the liquid sample can be estimated. The usefulness and validity of this new laser flash technique have been confirmed by obtaining the thermal diffusivity values of silicate melts in the wide temperature range between 773 and 1673 K.

Jan 1, 2003

By Masaaki Naito

The Japanese steel industry has a long history of introducing new and innovative technologies in the field of ironmaking. The new technologies introduced during the past ten years include technologies to use cheaper and lower-grade raw materials and fuels, measures to prolong the service life of blast furnaces and coke ovens, promotion of energy saving, use of wastes and solutions to environmental problems. This report outlines the condition of production and technological trends and technical development themes in ironmaking technologies.

Jan 1, 2006

By I. Ueda, S. Ishikawa, T. Nagata

“O-SR process” in which the S-Furnace of the Mitsubishi process is followed by existing reverberatory furnaces (RFs) and Peirce Smith (PS) converters has been operated since December 2007. The S-Furnace smelts copper concentrates to produce molten matte containing 58-62%Cu which is then settled in the RFs and converted to blister copper in the PS converters. The SO2 gas generated from the S-Furnace and PS converters is converted to sulfuric acid in the acid plants. In addition to the smelting copper concentrates, the O-SR process has advantages in terms of recycling various waste/secondary materials. Automotive Shredder Residue (ASR) has been treated in the RF to reduce fossil-fuel consumption in RFs, and to recover various metals included in ASR as well, since 1993. Electronic circuit boards (E-scrap) has also been processed in order to recover not only copper but also rare resources such as gold, silver and PGMs since 2013. Strategic modifications have enabled expansion of the processing volume of E-scrap. Enhancing recycling of wastes and scraps from urban mines while reducing the consumption of natural resources in the “O-SR” process will be demonstrated and discussed in the present paper. INTRODUCTION Onahama smelter and refinery has been operating as a custom smelter since 1965. Smelting facilities were subsequently expanded to two green-charged RF furnaces and five PS converters in 1973. Since RF is a conventional old-fashioned smelting furnace that necessarily consumes a huge amount of fuel to smelt copper concentrates, saving fuel cost has been an important objective. In early 1980’s the fuel was changed from bunker oil to pulverized coal, while utilizing the combustion heat of waste tires. Furthermore, treatment of combustible waste such as shredder residue (SR) was initiated in order to save fossil fuel for smelting concentrates in the RFs. Since enhancing of the treatment of SR requires a reduction in concentrate smelted in the RFs, most concentrates were dried and injected through tuyeres into the PS.converters. These modifications enabled to reduce the amount of the pulverized coal combustion and to increase SR treatment in the RFs. SR treatment capacity has increased to 12,000mt/month because the SR market has grown after the enforcement of the Vehicles Recycling Law. Such business environment has been attributed to establish the thermal-materials recycling system of SR in which the RFs have changed their role from copper concentrates smelting furnaces to waste materials combustion furnaces.

Jan 1, 2019

By Martti Hagfors

UNDERWATER EXPLOSIONS - Part 6 - EFFCTS OF CYLINDERICAL SHAPE OF CHARGE TO THE RESULTS OF ENERGY MEASUREMENTS OF EXPLOSIVES

Jan 1, 2008

By R. Wharton, M. Bagley

Following a series of papers relating to the certification of explosives for sale in member states of the European Union presented at previous ISEE conferences, this poster paper has been prepared to stimulate discussion and debate on the recently published European Directive on Pyrotechnic Articles.

Jan 1, 2008

By Jack Curran

KANSAS CITY, MO - Performing one of the most impressive urban building-implosion projects in recent memory, Tulsa, Oklahoma-based Dykon Explosive Demolition Corp. and Omaha, Nebraska-based Anderson Excavating recently felled the landmark Columbia Bank Building in downtown Kansas City, Missouri, USA. Although every structural blasting project presents special challenges, this undertaking was most notable for its unusually unique structural design, tight clearances, and high risk to adjacent structures.

Jan 1, 2003

By Brent Blanchard

As most veterans of our industry are aware, explosive demolition by its very nature is often a challenging proposition. Even under the best of circumstances, proper planning and care must be taken during a variety of processes to ensure a safe, successful result. However, every now and then a project suddenly arises where safety, timing and cost factors combine to form a critical scenario requiring rapid execution in an environment far more challenging than the norm. On these occasions, the stresses, complications - and most notably the dangers - related to the industry increase exponentially, and conspire to test the mettle of even the most seasoned experts.

Jan 1, 2003

By Stacy Loizeaux

The Beirut Hilton Hotel, which was built in 1975, but never occupied, was imploded on Sunday, July 14, 2002 by Controlled Demolition, Inc. (CDI) of Phoenix, Maryland and their client, Optimal Engineering Consulting & Contracting, SARL, (OECC) of Antelias, Lebanon to make room for a new hotel. Twenty-seven years ago, just days before the grand opening, the Hilton Hotel became the site of fighting in Lebanon’s Civil War. Christian and Muslim militiamen fought room to room for control of the building and other nearby hotels. The Hilton, two other major hotels and other high-rise buildings were ravaged by the fighting. The building was one of the three major hotels badly damaged, but not rebuilt, in Lebanon. Located in the City Center, the Hilton stood out in a major redevelopment area which, in recent years, had erased the scars of the 15 year long Civil Wa r.

Jan 1, 2003

By Brent Blanchard

Dallas/Fort Worth Airport recently took a major step in its fiveyear expansion project with the explosive demolition of the Hyatt Regency Hotel West. Built in 1965, the Hyatt Regency held the distinction of hosting five U.S. Presidents over the years and was reportedly one of the first hotels in the world to be built within an airport’s boundaries.

Jan 1, 2003

By Bert Bahnson

As farms decrease and subdivisions increase there is a continuing demand for easy and safe silo removal. A few years ago I attended one of the Omni istribution explosive classes and was impressed by a product designed by Omni owner Bill Nixon called the Omni Breach. Its original purpose and main current use is law enforcement; specifically door breaching and tactical operations, with most of the force coming from water using a minimal amount of explosive component. I experimented with various charge strengths on concrete and found that it can be easily shattered with little flyrock or airblast. A neighbor of mine had an old silo within a foot of a barn that he was rebuilding and inquired about its removal. His property was sandwiched between an elementary school and Interstate 40, so I told him that I would do some test shots and if the results proved satisfactory, I would take the job for free to test the following theory.

Jan 1, 2006

By Jacolien P. Wyethe

Zincor uses a Roast-Leach-Electrowinning circuit to process zinc sulphide concentrates. It also processes zinc oxide fume, originating from a slag smelting operation in the Democratic Republic of the Congo (DRC). Zincor achieved an average zinc recovery of 90.3% during the period January 2006 to May 2007. The bulk of the losses occurred in the iron and lead silver residues, both as soluble and un-dissolved losses. The un-dissolved losses in the iron residue constituted around 33% of the total zinc lost from the circuit, and were largely attributed to the presence of zinc-ferrite in the calcine used for neutralization during iron removal. As part of Zincor?s continuous improvement programme, the un-dissolved zinc losses in the iron residue were targeted by: the partial replacement of calcine with zinc oxide fume (from the DRC); and the preferential use of ?low-ferrite content calcine? as neutralizing agents in the iron removal circuit. These initiatives, coupled with other operational factors, resulted in a marked improvement in recovery to 92.6% during June to December 2007. The zinc oxide fume, directly fed to the circuit, required investigation of the halide rejection capacity of the Zincor circuit. Rejection of chloride via the magnesium bleed operation was considered adequate. Fluoride was mainly rejected via the iron (~70%) and lead silver (~27%) residues. Fluoride rejection via the lead silver residue varied significantly, probably as a result of variations in the sparingly soluble CaF2 content in the feed. The mechanism for fluoride rejection in the iron residues is uncertain. The fluoride rejection capacity of the Zincor iron residue (comprising of mainly jarosites, schwertmannite and ferrihydrite) at 2 ? 4 mg/L F in solution, was estimated at 0.14 ? 0.19 kgF/tFe residue.

Jan 1, 2008

By David J. Forrester

"CANMET’s research into underground coal mining is primarily conducted at the Cape Breton Coal Research Laboratory (CBCRL), established in 1981 to conduct safety research in underground coal mines. Located close to Canada’s largest underground coal producer, in the Sydney Coalfield of Nova Scotia, CBCRL’s program also includes the two western underground coal operations. CBCRL is a relatively small laboratory with a staff of thirteen — eight professionals and five support staff — with an annual budget of over $1 million. In order to maintain effective research response, flexibility is key and staff are increasingly working in project teams, crossing traditional section ties and also drawing from specialist expertise elsewhere within CANMET.CBCRL’s research activities have had a substantial impact on the Canadian underground coal mining industry, particularly in Cape Breton. CBCRL contributed to Cape Breton Development Corporation’s (CBDC’s) threefold reduction in lost-time accidents in the 1980s. Also, in the last four years alone, CBCRL’s work has enabled CBDC to save over $17 million in improved utilisation of reserves and cost savings. The work embraces the three traditional areas of mine environment, strata mechanics and mining technologies, however the current direction has been strongly influenced by recent external and internal factors. It is timely to review progress and recent directions."

Jan 1, 1996