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By A. T. Sweet, G. Douglas Gardner

"INTRODUCTION In the ammonium sulfate process for the production of alumina from clay,,3/ the clay is baked with amonium sulfate at about 400ºC. to form anhydrous ammonium alum and free ammonia or ammonium carbonate. The alum is leached from the baked product with water and circulating liquors and is purified by recrystallization. Aluminum hydroxide is precipitated by treating thus alum the alum the ammonia or ammonium carbonate from the baking step. Ammonium sulfate is recovered from the filtrate for reuse, and the aluminum hydroxide precipitate is calcined to produce high-purity alumina. In this process, as in other acid processes for the production of alumina, 4/ a large part of the iron in the clay is extracted. The iron tends to build up in the leach liquors and contaminate the crystals, so that its elimination is one of the most important problems in the process. A number of large clay deposits occur in the Western States. Those that have boon explored most extensively 5/contain an average of 24 to 30 percent available A12O3 and 2 to 8 percent available Fe2O3. 6/ The available Fe2O3 content of various other clays ranges from less than I percent to more than 20 percent. The available Al2O3 or Fe2O3 is usually 90 to 98 percent of the total but may be much less. In generals the iron content bears no fixed relation to the alumina content and may vary widely within a given deposit."

Jan 1, 1948

By Gary W. Krantz

Fibered, portland-cement-based gunite products were applied in the Bureau of Mines Lake Lynn Laboratory Experimental Mine using a variety of pneumatic guns and gunning crews, The demonstrated wet-mix (with silica fume), dry-mix, and surface bonding products were sampled by the Bureau and subjected to a suite of engineering analyses. Gunite flexural and compressive strength, rebound, permeability, porosity, dust loading, shooting rate, crew requirements, and cost factors were evaluated. Steel, fiberglass, or polypropylene fibers were contained in all but two of the gunires tested. Both Bureau and private testing laboratory analyses are provided for some products. Electron probe micro-analysis and X-ray diffraction analysis were performed on the silica fume fraction of the wet-mix gunite to characterize the dust. Aggregate size fraction distribution analyses were performed to provide strength relationships. Results indicate that all of the commercially available fibered-gunite materials tested can provide beneficial sealant, spall prevention, or roof stability control attributes for underground mining environments when applied by an experienced crew using a well-maintained gun, in accordance with product manufacturers' recommendations and when used for the designated purpose.

Jan 1, 1984

By Etsuro Shibata

The saturated solubility of chromium oxide and the valence of chromium in the slag are important matters when considering how to effectively utilize chromium-containing slags. The experimental data of various types of slags cited in the literature were arranged according to the optical basicity in order to evaluate the effects of the oxygen potential and the slag composition. The saturated solubility of chromium oxide and the Cr2+/ Cr3+ ratio tend to decrease with the increase of the optical basicity of the slag at an oxygen potential below 10.5 atm. However, at an oxygen potential of 0.21 atm, the saturated solubility and the Cr6+/Cr3+ ratio tend to increase with an increase of the optical basicity. A practical approach was suggested to reduce chromium in the stainless steel slag and simultaneously recover it as a ferroalloy by the direct smelting reduction of chromium oxide in the molten slag using some reductant in a small furnace.

Jan 1, 2003

By C. A. Sutherland

"Smelting of copper-gold ore from nearby Rossland mines started at Trail in the 1890s. As ore from the Rossland mines became exhausted, lead smelting of hand-sorted galena ore from other British Columbia mines was initiated. With the development of flotation technology for the separation of lead, zinc, and iron sulphides in the first two decades of this century, the large Sullivan orebody at Kimberley, British Columbia, became the f oundation for the growth of a major zinc and lead smelter at Trail. Lead smelting began in 1901, electrolytic zinc in 1916, and by 1984, the Trail metallurgical complex had produced 10 million tons of each metal. Its present capacity is 270000 tonnes per year of zinc and 110 000 tonnes/year of lead.This paper reviews the history of technological changes in the Trail production plants, emphasizing the zinc plant modernization program started in the 1970s, and also the planned introduction of the QSL oxygen lead smelting process in the late 1980s. Lead modernization will increase production capacity to a maximum of 160000 tonnes per year.IntroductionCopper-gold ore was discovered at Rossland, British Columbia, in the year 1890, starting a mining industry that was to last over three decade s. Selected ore was at first transported at high cost to distant U.S. smelters, so there naturally followed a decision to construct a small copper smelter to process the local ore to matte. It was built in 1896 at the mouth of Trail Creek on the Columbia River, about 10 km from Rossland. This little smelter was to develop and diversify in the next 90 years into the world 's largest lead-zinc producer).The mining boom that occurred in the northwestern United States and southeastern British Columbia in the period of 1890 to 1910 saw the brief operation of many small local smelters. The only one to survive was the smelter at Trail. The circumstances that permitted its continued life and subsequent growth, form a fascinating history of business deals, litigation, andsteady technical progress.Early investment in local railway transportation and options by F.A. Heinze, the smelter' s founder, attracted the attention of the Canadian Pacific Railway Company, which purchased Heinze' s assets in 1898. This provided the capital base for survival and growth of the smelter, which remained and prospered under the Canadian Pacific umbrella for almost ninety years. It was registered as the Consolidated Mining and Smelting Company of Canada Limited in 1906; in 1966, this name wasshortened to Cominco Ltd.The Rossland mines continued to supply copper ore for the smelter until the late 1920s, but lead-silver ore also became available from the contemporary mining boom in the Slocan area, about 80 km away. In 1901, the Trail smelter diversified into lead; and when the CM&S Co. acquired the St. Eugene Mine at Moyie and the Sullivan Mine at Kimberley, the smelter was guaranteed a firm supply of lead ore. The company also purchased the West Kootenay Power and Light Company, which even before the turn of the century had constructed the first of four hydroelectric generating plants on the Kootenay River near Trail. This acquisition assured the CM&S smelter and its local mines of a stable power supply and the opportunity to diversify into power intensive technology."

Jan 1, 1988

By John Plecash

This paper comprises a general outline of all of the developments, including the history, geology, mining, milling, power and transportation installations, at the gold mining operation of La Luz Mines Limited and the copper mining operation of its wholly-owned subsidiary, Rosita Mines Limited, both located in north-central Nicaragua. The low-grade, gold-bearing ore-bodies of La Luz Mines, contained in highly fractured and folded Lower Cretaceous sedimentary rocks, were from 1909 to 1928, mined and treated by primitive methods by the La Luz and Los Angeles Mining Company. The abandoned property was acquired by La Luz Mines Limited in 1936, and was equipped with modern machinery and put into production in 1939. Between 1939 and 1948, the daily rate of production was in-creased from 300 tons per day to 2,-000 ton per day. The ore reserves available for open-pit mining were depleted in 1954. Since then, the entire production has come from under-ground operations.

Jan 1, 1963

By T. Lupek, S. Plaum

"The execution of classical building services in underground mining operations is more truth than myth. From small concrete foundations for conveyor belts to the construction of huge workshops for large machinery maintenance, nearly every operation requires building services. By creating such fixed facilities, these services ensure the efficiency of the production. A distinction must be made between fixed facilities which directly enable the production and auxiliary facilities which only indirectly support the production. The construction costs of such auxiliary facilities are often roughly estimated because they do not immediately contribute to mineral extraction. The research project ‘Development of a systematic cost-calculation method for building services in underground mines’ seeks to address the question: ‘Can the construction costs concerning fixed auxiliary facilities be neglected e.g. within a prefeasibility study?’ The presentation will show the monetary relevance and significance of these auxiliary facilities and introduce a guideline for cost estimators. PROBLEM DEFINITION The overriding interest of an underground mining operator is to exploit the commodity with the maximal quality by minimum cost and time expenditure. If a new operation shall be installed, it has to promise profitability. Therefore, predictive economic feasibility studies are performed in advance of installation. Herein, all cost expenditure for installation and operation of the future underground mine is determined and compared to the expected income by selling the raw material. The described interest of the mining operator is the starting point of the research project ‘Development of a systematic cost-calculation method for building services in underground mines’. While economic feasibility studies for future operations are focused on the profitable exploitation of raw materials and the efficiency of the accompanying necessary production processes, auxiliary actions are only considered rudimentary. Necessary production processes, as well as auxiliary actions regularly require classical building services, which are normally performed in construction business on the surface in the same manner. By performing building services like masonry or concrete works in underground mines, fixed facilities shall be set up in order to enable or support the raw material production. Production enabling fixed facilities are varying from small concrete foundations for conveyor belts or other infrastructural elements to upstream processing plants situated in the mine workings. While such fixed facilities are essential parts of the production process chain, supporting facilities underground shall increase the efficiency of the mining operation. Workshops, control rooms and social installations are only a few examples for supporting facilities. Those could be situated on the surface as well, but the efficiency increases significantly by installing them underground. Especially supporting facilities are evading from the main interest of the mine operator, since they are only indirectly connected to the production process. The building costs are oftentimes only roughly assumed."

Jan 1, 2017

By Zhengjie Chen, Wenhui Ma, Jijun Wu, Kuixian Wei

The gasification reactivity of PC (petroleum coke), strengthened by addition of different potassium carbonate proportions using different grinding medium, was investigated by using thermogravimetric analysis (TGA). Results showed that the gasification reactivity of PC not only increased with the increase of catalyst-loaded, but also showed the effective improvement by anhydrous alcohol. The PC was mixed with potassium carbonate [K2CO3] catalyst at 0.5%, 0.8%, 1.0% and 1.5%, and then ground wet with distilled water. The CO2-gasification rate of PC was only 77.35%, 80.55%, 84.07% and 85.88% under the gasification temperature 1100 °C and holding time 120 min, at different K2CO3 respectively. However, when the PC was ground in anhydrous alcohol at the same condition of catalyst-loading, the gasification rate of PC reached 95.43%, 96.63%, 95.50% and 95.61% at the holding time of 108 min, 101 min, 74 min and 35 min, respectively. It was shown by FTIR, SEM and EDX determinations that the anhydrous alcohol used as the grinding medium can further improve the gasification reactivity of PC when compared with the distilled water.

Jan 1, 2016

United Engineering Trustees, Inc. WILLIAM H. BASSETT H. G. MOULTON R. M. ROOSEVELT The Engineering Foundation GEORGE D. BARRON E. DEGOLYER R. M. ROOSEVELT Engineering Societies Library Board ROBERT PEELE H. K MASTERS A. B. PARSONS, Ex-officio F. F. SHARPLESS R. H. SWEETEST

Jan 1, 1934

By G. M. Ritcey

The recovery of copper from low-grade solutions res ulting from dump leaching is well known, whereas the recovery from highly concentrated copper solutions has not been practiced. This paper discusses the use of Ashland Chemical's Kelex 100, a substituted quinoline, for the recovery of copper from solutions resulting from leaching copper-nickel concentrates. A flow sheet is described, and an economic comparison shows Kelex 100 to be superior to either the LIX 64N or LIX 70 reagents of General Mills for the recovery of copper.

Jan 1, 1973

By Michael S. Moats, John Bailey Fletcher

Wear rates of grinding media can be misrepresented by marked ball wear tests (MBWT). Galvanic interactions between dissimilar grinding media can be affected by the chromium content in the media and the presence of oxygen in the environment. Corrosion, one component of wear, can be affected by many variables. Corrosion rates and corrosion potentials for modern high chromium white iron (HCWI) and high carbon steel (HCS) grinding media samples were obtained through electrochemical testing. In this study, the impact of chromium content in the grinding media and the dissolved oxygen in a simulated mill water solution on corrosion rates and potentials was examined. Increasing chromium content in HCWI above 15 weight percent increases the corrosion potential and decreases corrosion rate. Removing most of the oxygen from the solution lowers both the corrosion potential and corrosion rate of the materials tested. The electrochemical results were examined to model possible galvanic coupling effects on corrosion rates. Galvanic coupling between HCS and HCWI could cause differences in corrosion rates for almost all scenarios modeled. Based on the galvanic coupling analysis, MBWT results could be impacted by mixing HCWI and HCS in a ball mill charge. This impact is predicted to be more significant when dissolved oxygen is present in the mill water and as the chromium content of HCWI is above 15 weight percent.

Dec 21, 2022

By C. A. Sutherland

"Smelting of copper-gold ore from nearby Rossland mines started at Trail in the 1890s. As ore from the Rossland mines became exhausted, lead smelting offhand-sorted galena orefrom other British Columbia mines was initiated. With the development of flotation technology for the separation of lead, zinc, and iron sulphides in the first two decades of this century, the large Sullivan orebody at Kimberley, British Columbia, became the foundation for the growth of a major zinc and lead smelter at Trail. Lead smelting began in 1901, electrolytic zinc in 1916, and by 1984, the Trail metallurgical complex had produced 10 million tons of each metal. Its present capacity is 270000 tonnes per year of zinc and 110 000 tonnes/year of lead.This paper reviews the history of technological changes in the Trail production plants, emphasizing the zinc plant modernization program started in the 1970s, and also the planned introduction of the QSL oxygen lead smelting process in the late 1980s. Lead modernization will increase production capacity to a maximum of 160000 tonnes per year.IntroductionCopper-gold ore was discovered at Rossland, British Columbia, in the year 1890, starting a mining industry that was to last over three decade s. Selected ore was at first transported at high cost to distant U.S. smelters, so there naturally followed a decision to construct a small copper smelter to process the local ore to matte. It was built in 1896 at the mouth of Trail Creek on the Columbia River, about 10 km from Rossland. This little smelter was to develop and diversify in the next 90 years into the world's largest lead-zinc produce.The mining boom that occurred in the northwestern United States and southeastern British Columbia in the period of 1890 to 1910 saw the brief operation of many small local smelters. The only one to survive was the smelter at Trail. The circumstances that permitted its continued life and subsequent growth, form a fascinating history of business deals, litigation, and steady technical progress.Early investment in local railway transportation and options by F.A. Heinze, the smelter' s founder, attracted the attention of the Canadian Pacific Railway Company, which purchased Heinze' s assets in 1898. This provided the capital base for survival and growth of the smelter, which remained and prospered under the Canadian Pacific umbrella for almost ninety years. It was registered as the Consolidated Mining and Smelting Company of Canada Limited in 1906; in 1966, this name was shortened to Cominco Ltd."

Jan 1, 1988

By D. E. Cameron

"INTRODUCTION Grade control requirements for base and precious metal projects are an important input to both conceptual and feasibility mine plans. It’s the author’s experience that grade control input is insufficient at these critical stages. The few exceptions are a stimulus for this paper. A significant portion of CRC’s practice has involved assisting operations to solve grade control issues which were finally recognized as contributing to negative production variances. Even in operations perceived to be successful, deficiencies in grade control are often masked by measures taken by an operation to compensate a deficiency in one area with outperformance in another. The advantages in having a realistic and adequate grade control plan developed at an early project stage by a geologist(s) with considerable operations experience are manifold. It’s important for the geologist to prepare clear inputs into the mine plan backed by detailed supporting information in usable, flexible formats. When the decision is made to advance a project, the exploration team passes its model to a mine planner. The team doesn’t usually provide a detailed grade control plan with the block model, thus the planner tends to treat grade control as an activity to be rolled into a broader operating category. The consequences of highly compartmentalized mine planning can be severe in the long run. Once a plan is tabled, and especially once production begins, it is very difficult to improve grade control outside the fixed parameters of the operation. Major fixes tend to be costly in terms of time and dollars. Implementing needed changes to the grade control practices and culture in an established mine can present almost insurmountable difficulties. Hypothetical examples of grade control planning are presented to illustrate the author’s points. The diagrams are conceptual and schematic; any resemblance to actual deposits is coincidental. BEYOND 50¢/TON In more than a few cases, grade control cost is buried in a subcategory of mining cost with little more consideration than a plugged number. It is possible to do a word search in 43-101 Technical Reports on advanced projects and without finding reference to “ore control” or “grade control”. The idea is to reach the orebody by the shortest and least expensive means, achieving production and investor payback at the earliest possible occasion. This entails a low stripping ratio pit or a decline ramp with sills on ore to prepare the first stopes. The processes to achieve the target production, one of which is grade control, will fit into this framework. After all, there is a block model and the planner can see the grade and tons in each block. The exploration geologist whose responsibility was to bring a large percentage of the deposit into mineral resource owns the model and has released it to planning. Now comes the planning stage. Mine geologists haven’t been hired yet and they will be phased in with production. What could go wrong? Larger companies may have the geologists with operating depth who will be inserted into the mine planning discussions, but it’s not a given. Junior companies must often delegate the conceptual and detailed planning tasks to consultant groups. Is a senior-level grade control review part of the scope of work for the mine planning? If a good grade control plan is in place before the mine geology team is staffed, a key element of success is assured."

Jan 1, 2018

This listing of members is arranged to show company affiliation The primary breakdown is by state or country, then by company name and political subdivision At the end of each major group is a general list showing members affiliated with schools or colleges and those who did not indicate any company affiliation The listing, for countries outside United States, is broken down generally by continents and alphabetically within the continent by countries The various countries are indexed on the preced¬ing page *-The asterisk indicates members available for consulting work Anyone desiring to be listed with AIME as available for consulting work can do so by sending a written request to the office of the Secretary.

Jan 1, 1952

By E. W. Dean

This report on the physical and chemical properties of typical crude oils of Oklahoma is the sixth in a series of preliminary chapters of a bulletin covering the producing districts of the United. States. Preceding reports* may be obtained on request. The details of the methods used in this survey in collecting samples, making laboratory tests, and interpreting results are discussed in the first three papers. If any errors or omissions are noted by readers, it is hoped they will be brought to the attention of the Bureau of Mines for correction before the appearance of the permanent report. Samples of Oklahoma crudes analyzed in this report were taken from those fields representing the major production of the State. The Oklahoma Geological Survey designates 172 different oil and gas fields in the State, S1 being in Osage County, 14 in Tulsa County, 14 in Okmulgee County, 9 in Washington County. The list of samples collected by the Bureau of Mines represents only 5 fields in Osage County - Bigheart, Burbank, Hominy, Osage Junction, and Pershing - yet these samples, together with those from adjoining fields, are representative of nearly all crude produced in the county. The sample 'from the Pershing field, for example, is representative of the crude produced in several fields in that part of the county - such as Nelagoney, Pawhuska, Wyomona - and the sample from the Skiatook,

Jan 1, 1922

By Y Nagendra, A. Ravi Kumar

A breakwater is a construction for protecting the marine structures like port, harbor, or anchorage-basin and berthed marine vessels from the destructive influence of the sea waves. The breakwater is constructed by using geologically competent, heavy, massive rock like granite, basalt etc having physical and mechanical properties within the limits specified by the designers. The construction requires boulders in varying sizes ranging from 0.5 kg to 20,000 kg. The stones from 0.5 to 1000 kg are called as core fill and boulders greater than 1000 kg are termed as armor blocks. These armor blocks cover and protect the core fill and prevent it from escaping. The requirement of armor blocks ranges between 25 to 35 %. The rest is core fill. However, the actual requirement depends on the breakwater design. In this context, the task of the mining engineer is to economically produce armor blocks and core from the designated quarry in right proportion with minimal losses. The whole bunch of engineering ingenuities should be put forth for obtaining the required armor blocks. The armor block production from any blast depends chiefly on geological conditions, bench dimensions and blast design. This paper is an attempt to bring out the various parameters affecting the performance of the blasting for armor block production using a case study.

Jan 1, 2005

By Jarrell C. Grout

The Bureau of Mines has developed a computer program for use in solving nonlinear regression problems. The program is written in a general form so that, regardless of the functional relationship, the unknown parameters may be evaluated by either the Gauss-Newton or the Newton-Raphson methods of iteration. Variances and covariances of the parameters, as derived from the law for the propagation of errors, are also determined.

Jan 1, 1969

By L. V. Kin, V. V. Lodeischikov, A. V. Byvaltsev, IRGIREDMET JSC, O. D. Khmelnitskaya, S. V. Petrov

"Irgiredmet Institute carried out the study on the development of gold recovery technology from refractory ore from a Russian deposit. The ore contained 1.1 g/t Au, 1.5% of pyrite and 2.4% of pyrrhotite. The recovery of gold achieved was 84.7% using gravity with generation of high grade recoverable gold concentrate and gravity middling. In the course of lime treatment, cyanidation of the middling followed by tailings detoxification the consumption of reagents was 13.0 kg/t CaO, 95 kg/t NaCN and 72 kg/t Ca(OCl)2 of the concentrate. This was capital intensive.In order to decrease the consumption of reagents, magnetic separation of the middling of the concentrates from gravity separation was added to this flow sheet. Pyrrotite recovered to magnetic fraction, which did not contain gold in accordance to this advanced flow sheet. The mass yield of pyrite goldbearing non-magnetic fraction decreased down to 1.5 times in relative to gravity middling. The slurry filtration prior to and after cyanidation allowed the organization of cyanide solution recycling.The results of pilot plant tests using the developed flow sheet showed that the content of pyrrhotite in the non-magnetic fraction decreased from 59.1% to 11.3%. The reagents consumption was 12 kg/t CaO, 3 kg/t NaCN and 16 kg/t Ca(OCl)2 of the pyrite concentrate. The total gold recovery using this flow sheet was 83.4%. Due to a decreased consumption of reagents, cost efficiency of the process was achieved. Based on the results of this research, a project design criteria was developed. A processing plant with the annual throughput of 2.6 million tonnes of ore is being designed."

Jan 1, 2016

By J. J. deBarbadillo

This Bureau of Mines report describes a process for recovering chromium and other metals from superalloy scrap. Laboratory-scale experiments were conducted to test a complex flowsheet utilizing a wide range of extractive metallurgical operations. The novel basis for the process is the fonnation of a sulfide matte in which chromium is concentrated in a discrete chromium sulfide phase. Mineral processing and hydrometallurgical procedures are used to separate chromium sulfide from the other matte constituents. The products of the process are a chromium-nickel alloy suitable for reuse in the superalloy industry, electrolytic nickel, electrolytic cobalt, and iron-molybdenum residue. Recovery of the principal elements contained in the scrap is chromium--93 percent, nickel--99 percent, cobalt--96 percent, and molybdenum--92 percent.

Jan 1, 1981

By Jack L. Henry

A laboratory and a pilot-plant-scale investigation has been conducted by the Bureau of Mines to examine possible sources of nitride defects in the production of magnesium-reduced titanium sponge. The production of alpha-stabilized nitride inclusions in hot-rolled titanium plate from air contamination of sponge during its manufacture has been experimentally demonstrated. Magnesium-reduced sponge prepared from air-contaminated magnesium or when contaminated by an air leak during reduction, vacuum distillation, or inert gas sweep, shows very large variations in nitrogen content. Refractory nitrides, delta TiN and epsilon Ti2N have been identified in this sponge. The highest incidence of inclusions resulted from sponge that was reduced by air-contaminated magnesium and from sponge subjected to air contamination during the vacuum distillation cycle and during helium sweep. Air contamination of sponge during the reduction cycle was not nearly as effective in producing inclusions. Tests showed that color and texture may not be reliable criteria for locating defects during sponge inspection. Maintenance of good vacuum-tight integrity, filtration of molten magnesium prior to charging into the reduction retort, and mechanical attrition of sponge to pulverize and disperse nitrides are suggested as practices to lower inclusion incidence in commercial titanium ingots.

Jan 1, 1974

By K McLeod

{Figure 1} The Placer Dome-Western Areas Joint Venture?s South Deep Twin Shaft Complex, has been planned and dreamt of for nearly 20 years. [ ] The gold reserve at the bottom of these shafts is one of the largest single intact gold deposits remaining in the world today, containing an estimated 57 million ounces. This is about the size of the fictitious reserve created by inventive prospectors for the infamous BREEX scam in Kalimantan about ten years ago and about the size of the reserve Harmony claims as its own in it?s current hostile takeover bid for Gold Fields. So it is certainly of the magnitude that dreams are made of. [ ] {Figure 2} The unique orebody lies in a continuous, highly concentrated, thick deposit, an estimated twelve kilometres along dip and a two kilometre wide strike. Due to the thickness of some sections of the reef, up to 60 metres in places, bulk mining methods will be required for it?s extraction. [ ] {Figure 3} The twin shaft system comprises a main shaft which had an initial design depth of 2765m and a ventilation shaft of 2760m, making them the world?s deepest to be sunk in a single lift. The shafts were

Jan 1, 2005