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By R. L. Grant

[Detonators are used to explode permissible explosives, dynamites, or other high explosives. This explosion or detonation is brought about by the energy which is liberated as a combination of concussion and heat when the detonator is fired. In Other words; "The detonator is the key which unlocks the energy of a high explosive" (8)4. Being sensitive and latently dangerous, detonators must meet two primary requirements: They must be safe to handle and must detonate when desired, thereby imparting detonation to the explosive charge.]

Jan 1, 1941

By Ralph Dawson

The following additions to SLP-4 “ALWAYS AND NEVERS” have been approved by the Board of Governors since the last printing 6/97 and will be included in the next printing soon. They are also included in the Second Printing of the 17th Edition of the ISEE Blasters Handbook. Review them and apply those which might be applicable into your blasting program now.

Jan 1, 2001

By M. C. Irani

This survey was conducted to determine the magnitude of the methane emission and control problem in U.S. bituminous coal mines. The resultant data indicate that the emission rate for any given coalbed depends primarily on the coal production rate and on mine depth, as well as on the nature of the coalbed and the surrounding strata. An excellent correlation was found between (1) the methane emission rate and (2) the product of coal production rate and mine depth for the mines in the Pittsburgh, Pocahontas Nos. 3 and 4, and the Illinois Nos. 5 and 6 coalbeds. The highest total emission rates found in U.S. bituminous coal mines were as follows, in million cubic feet per day: Monongalia County, W. Va., 39; Marion County, W. Va., 30.4; McDowell County, W. Va., 13.1; Washington County, Pa., 11.9; Greene County, Pa., 11.4; Buchanan County, Va., 21.6; Jefferson County, Ala., 10.3; and Franklin County, Ill., 6.6.

Jan 1, 1972

By James C. Fowler

This report contains a description of the contract activities performed by ENSCO, Inc. under contract H0292025. The purpose of this project was to prove the feasibility of detecting hazards in a coal seam using a synthetic pulse radar. This work was conducted in three phases. The first was an analysis of the types of errors which might cause problems. The second was to build a breadboard radar and the third phase was to conduct a field test with the system. The work from each phase is discussed and the results of the field tests are presented. These results show propagation of the radar signal through 200 feet of coal along with reflections from 50 feet away. The final section contains recommendations for future development.

Jan 1, 1981

A poured slag bottom is universally considered to be the best type bottom for copper reverberatory furnaces. It is impervious to molten matte and ready for immediate use.When molten slag is not available a monolithic silica bottom is the second best; such a bottom has been adopted at Mount Morgan. The laying of such a bottom is a phase of smelter construction on which so little real information is obtainable that a day to day record of such a recent example as Mt. Morgan's 19 ft. x 40 ft. reverberatory may be of interest. The work was done under the direction of E. Pesout, of McGill Smelter, Nevada. PREPARATION OF THE BOTTOMA 26-inch bed of closely packed firebrick with sand-filled joints was first laid on the clean, dry concrete foundation and the whole dried out by small fires maintained on the brickwork for several days. Ninety tons of silica sand was meantime thoroughly dried and stored in clean drums. This sand must be low in FeO and CaO and contain about 95% Si02 , the majority of which should be present as tridymite. This form of silica shows little expansion at high temperatures, for it is the form stable between 870° and 1470° C.Its presence thus minimises disturbance to the bottom by the expansion which, during the burning in, would mark the transformation of quartz to tridymite.

Jan 1, 1939

By J. Um, B. Morin, P. H. S. W. Kulatilake

Development of a three-dimensional mine visualization model for a section of the mine is addressed first. Discontinuity orientation and location information was taken from this visualization model for use in slope stability analyses. Estimated shear strength properties of discontinuities and mechanical properties of intact rock from the rock mass samples obtained from the mine are discussed next. The paper is then focused on the calculated maximum safe slope angles based on the performed kinematic and block theory analyses using the mapped discontinuities at the mine. Finally, the effects of water that exist in the rock mass, tension cracks, slope face inclination, overall wedge height and double benching on factor of safety of wedge stability are illustrated through limit equilibrium slope stability analyses.

Jan 1, 2002

At the inception of the gold-mining industry at Kalgoorlie the small supply of firewood required for steaming purposes was naturally all drawn from the limited local areas, which promised soon to become denuded. With the advent of the railway toKalgoorlie came the ever increasing machinery and steam power, and the accompanying demand for firewood so increased that the fuel contractors began their operations, by following the timber belts along the Yilgarn railway line, and graduallygetting further westward, until at present we find them as far as Woolgangie, 63 miles from Kalgoorlie, and with the regular railway rates, I0. per ton per mile, this maybe considered the limit of payable timber at current rates. Although in the early days the reserve of timber along the railway line must have appeared as incalculable and inexhaustible as that of coal did in Europe a couple of centurys ago, the day is now near us when even this source will fail to meet the demands made upon it, for, although a good two years' supply is available or the areas under the axe, yet it is time to look ahead and find from whence the future supplies are to be drawn. Along the railways we find the zone of felling operations limited for want ofcommunication, and only such portions of the forests as are within six or seven miles of the railway come under the axe at present while virgin forests to the rear remain practically unexploited. It is only in the course of the past sixteen months that the firewood industry has developed...

Jan 1, 1901

By Bengt Fellenius

The conventional wave equation analysis without control of the representativeness of the parameters to the actual conditions does not provide accurate results. However, the representatives can be vastly improved by means of using the results of monitoring the dynamic response in a pile during driving. Dynamic monitoring displays the interaction of independent strain and acceleration measurements having directly propor­tional response to impacts, but inversely proportional response to re­flections from the soil. Examples are given and the CAPWAP method used to calculate from the measurements the dynamic pile and soil para­meters and mobilized soil resistance is outlined. The dynamic monitoring technique and analysis has been accepted internationally and been incor­porated into Building Codes. The prediction is offered that in five year's time, no major piling project will be undertaken without dynamic monitoring and analysis.

Jan 1, 1984

Author's Note: Since the paper on "All-Flotation at North Broken Hill Limited" was read and discussed, the metallurgical results obtained have conclusively justified the adoption of the All-Flotation treatment.At present the shipping grades of lead concentrate produced from North mine ore range between 74% and 75% Pb, carrying approximately 43 oz. Ag and 4.5%-5% Zn. The lead recovery in lead concentrate is recording 95%-96% of the lead content of crude ore, and the milling and treatment cost on 6400 tons crude ore perweek of 96 hours has dropped to 6s. 3.6d. per ton on ore. With an increased ore tonnage, and with a new mill, considerable further reduction in costs is certain.New flotation machines, with 30 in. vertical depth of overflow (instead of 42 in. depth), are now being tried for the secondary granular treatment, with advantageous results. The treatment to-day is practically the same as that outlined in the paper, excepting that additional concentrate is returned for retreatment in the existing units.(Signed) A. LOWRY.Mr. T. A. READ: The author states (page 356 of Proceedings, No. 79), "The sulphide ore itself was then comparatively coarsegrained, a fact which permitted ready concentration of the galena contents by means of jigs, tables, vanners, etc."

Jan 1, 1931

By A. Tylczak, C. Shook, A. Doogan-Smith, S. Loif, B. Hilscher, P. Nayak

"This paper discusses how to effectively conduct energy efficiency studies during the design of new mineral processing plants and plant expansions. Energy management studies for new plants are ideally conducted as part of the feasibility study, but can also be done at the detailed design stage prior to the purchasing of equipment. Energy management engineers work as part of the mineral processing plant design team.Such studies usually result in energy savings of approximately 3-8% of the predicted plant’s energy consumption and energy demand. Potential cost savings can be significant. A variety of mineral processing systems – crushing/grinding, pumping, materials handling, fans/blowers, compressed air, and others – are assessed within this study.Energy Management Information System (EMIS) studies can also be performed for the new plant or plant expansion, as an independent study. EMIS can be incorporated into the electrical and controls design of the plant.Most Canadian Utility companies fund new plant design studies and provide financial incentives based on the predicted energy savings and incremental cost of the more energy-efficient design. A new plant energy efficiency study improves the potential for energy reduction because only the incremental equipment cost is included in the project return-on-investment calculation. After the design and construction phases, energy efficiency projects must justify the entire cost of the upgrade, which is significantly higher than the incremental cost alone.This paper outlines the major steps of a new plant/plant expansion energy efficiency study, the available utility company incentives, and the areas yielding the largest potential energy savings.IntroductionThis paper discusses energy efficiency studies and energy management systems with regards to mining operations. Energy management refers to the systems of monitoring, analyzing, and optimizing energy usage within a facility. It includes energy efficiency optimization of the initial plant design as well as the implementation of an Energy Management System (EnMS) and Energy Management Information System (EMIS) for optimizing energy usage over the lifetime of the facility. An EnMS is the organizational framework and procedures for managing energy use; an EMIS is the system of monitoring, reporting, and tracking process energy use against targets."

Jan 1, 2016

By W. R. Ingalls

THE following chronology presents the history of lead-mining in the United States in a brief form and is a useful reference in connection with the statistics of production 1621. Lead was mined and smelted near Falling Creek, Va., to supply the local demand for bullets and shot. This was the first mining and smelting of lead in what is now the United States. 1632. In a report made on the minerals of New England, lead-ore is mentioned. (Bishop, I., 470.) 1650. Supposed beginning of mining by Jesuits in Pima county, Ariz. 1651. Grant of lead-mine at Middletown, Conn., to Gov. John Winthrop.

Jan 9, 1907

By Jean Habimana

Complex and distinct geological units spread along the 7-mile long 30-ft inside diameter Upper Rouge Tunnel CSO Control Project in Detroit, Michigan. Its construction is divided in two tunnel construction packages: The South Tunnel, to be driven in finely laminated weak TG Limy Shale, will be excavated by a shielded TBM with precast concrete segmental lining, while the North tunnel, predominantly in a relatively more competent geologic formation Antrim Shale, will be excavated by a main beam TBM with a two-pass lining system. The adits and deaeration chambers will be excavated by sequential excavation method. This paper addresses the process of selecting excavation methods and lining systems for shafts, tunnels, connecting adits, and deaeration chambers.

By D. Mohapatra

The possibility of using 2,2,4-trimethyl-1,3-pentanediol dissolved in tetrachloromethane as extractant for boron recovery is discussed. The parameters optimized for this purpose are contact time, boron concentration in the aqueous phase, extractant concentration, equilibrium pH and phase ratio. NaOH is used as stripping agent for boron recovery from the loaded organic phase. Boron extraction is found to be a slow process (equilibrium time 20 minutes) compared to boron stripping, which is reasonably fast (equilibrium time 5 min). Maximum boron extraction is possible at a broad pH range from 1.0 to 6.0. Using 1.0M extractant concentration, a 1:1 phase ratio (organic: aqueous) and two stages, ~99% boron extraction is achieved. More than 97% boron stripping is possible using 0.5M NaOH at a 1:1 (organic: aqueous) phase ratio in two stages. Overall, a 95.6% boron recovery was achieved. Loss of solvent into the aqueous phase and co-extraction of Ca, Na and K into the organic phase at higher equilibrium pH are two major concerns in his process.

Jan 1, 2008

By Louise H. Michaud

Albian Sands Energy is scheduled to begin production at its oilsands operations in the fall of 2002. Start-up includes the selection and implementation of over 75 IT systems or computer applications. These include engineering applications, systems required to control mining activities, maintenance, the processing plant and utilities, and also systems required to run the company, such as human resources, finances and inventory/warehousing. This paper outlines the processes used for the selection, implementation and integration of these systems in order to optimize the use of information and to meet the technical, business and IT requirements of the company. The first step in Albian?s approach to identifying system requirements is the development of a Business Activity Model, outlining all tasks involved in running the operations. The computer applications required to accomplish each task are then identified by having the IT team work closely with each technical and business unit. Historically, at some companies, the selection of systems has been lead by the IT team or by consultants, with little input from the technical or business units. Typically, this results in products that don?t meet the company?s expectations. To ensure a more positive outcome, Albian believes that it is imperative that the company?s technical and business people are closely involved in the selection process. Integration of the IT systems is also key, including linking all applications through a Data Warehouse and EDMS. Over 120 required integrations have been identified. This ensures the storage of all data in only one location, data security, and easy data and document retrieval for all requirements throughout the company.

May 1, 2002

By Merwin H. Howes

Gnome shaft, situated about 24 miles southeast of Carlsbad, N. Mex., was designed and sunk by the U.S. Atomic Energy Commission for conducting a peace- time experimental nuclear explosion in the thick salt beds of the Permian Salado formation. Excavation was started July 1, 1960, and completed July 26, 1961. The 10-foot diameter shaft, lined with concrete through the rock section, was sunk 1,216 feet. A drift was driven approximately 1,140 feet on the 1,200- foot level terminating in a shot chamber. On completion of 100 feet of shaft, by means of a truck-mounted crane, facilities were installed for conventional sinking. About 709 feet of rock and 506 feet of salt were encountered in the shaft. Salt beds at this place are reported to be over 1,200 feet thick. The overlying rock section varies greatly in composition and thickness of beds and contains a 28-foot bed of water-bearing dolomite. The aquifer was sealed to facilitate shaft sinking and to prevent water-seepage damage in the salt section of the shaft. Sealing was accomplished by grout injection through holes drilled into the aquifer and by grouting behind the concrete liner.

Jan 1, 1963

By Merwin H. Howes

Gnome shaft, situated about 24 miles southeast of Carlsbad, N. Mex., was designed and sunk by the U.S. Atomic Energy Commission for conducting a peace-time experimental nuclear explosion in the thick salt beds of the Permian Salado formation. Excavation was started July 1, 1960, and completed July 26, 1961. The 10-foot diameter shaft, lined with concrete through the rock section, was sunk 1,216 feet. A drift was driven approximately 1,140 feet on the 1,200-foot level terminating in a shot chamber. On completion of 100 feet of shaft, by means of a truck-mounted crane, facilities were installed for conventional sinking. About 709 feet of rock and 506 feet of salt were encountered in the shaft. Salt beds at this place are reported to be over 1,200 feet thick. The overlying rock section varies greatly in composition and thickness of beds and contains a 28-foot bed of water-bearing dolomite. The aquifer was sealed to facilitate shaft sinking and to prevent water-seepage damage in the salt section of the shaft. Sealing was accomplished by grout injection through holes drilled into the aquifer and by grouting behind the concrete liner.

Jan 1, 1963

Research and Application of Vertical Screw Stirred Mill

Sep 13, 2010

Cessation of mining on the Bendigo goldfield makes it evident that, as the older generation fades away, knowledge of the famous Bendigo saddle reefs will be limited in the future by their written records. It is important therefore that the summarised account by D. E. Thomas (1953) in the Geology of Australian Ore Deposits should not be misleading. Fig. 6 in this article is stated to portray a cross section and longitudinal section through a series of gold shoots in the Garden Gully 300 ft. reef. The gold shoot along the capof the saddle reef is represented as extending down the east leg in a series of prongs, with the tips of the prongs about 50 ft. apart. It is the purpose of this note to indicate that this illustration can be suspected to be a diagram of the old stopes instead of a diagram of the distribution of gold in the quartz.The original sketches of Figs. 6 and 7 in Thomas' account were extracted, I believe, from the field note books of H. S. Whitelaw, years after his death in the late twenties. Whitelaw was stationed in the Bendigo office of the Geological Survey of Victoria, carrying out geological surveys of the Bendigo mines. He was there for many years before the Gold Research committee started its investigations in 1916 and he was acutely aware of the problem attached to the distribution of gold in the reefs. He had felt concern that manyauriferous reefs were being mined without adequate study and record and he decided, as he expressed it to me, to pick up what he could as he went along. There can be little doubt that the diagrams of Figs. 6 and 7 are products of this resolve.Opportunities to investigate gold occurrences at Bendigo were limited before 1916 because the field was operated by Manuscript received at The Institute 18th November, 1960.

Jan 1, 1961

By D. T. Holmes, W. G. Sandell

"INTRODUCTION Three representative lots of ore wore obtained from the Aguila minim district in Arizona during the Bureau's exploration of manganese deposits there. Since only selectively mined ore from this district will meet commercial-grade specifications, the ores were studied to determine their amenability to concentration.Although the purpose of the investigation was to determine the possibilities of the district as a source of commercial-grade manganese, testing was sufficiently comprehensive to indicate the response of the ores to several different types of treatment. Many data of secondary importance have been omitted, end only the more pertinent tests are presented in detail.At the beginning of the investigation of manganese-ore beneficiation in December 1940, the only product marketable to. Metals Reserve Company was ferro-grade manganese, grade B, the requirements for which follow: Mn, min., 48 percent; Fe, max., 7 percent; Si02, max., 10 percent; P, max., O.18 percent; Al12O3, max., 6 percent; Zn, max., 1 percent.Later the specifications were modified gradually. As of May 15, 1943, manganese products were acceptable if they contained over 35 percent manganese and less than 3 percent zinc and 1 percent phosphorus. Prices were based upon material containing 48 percent manganese, 6.O percent iron, and. 11 percent silica plus alumina. Premiums were paid for manganese con¬tent over 48 percent and iron content under 6 percent, penalties being imposed upon products containing loss than 48 percent manganese or more than 6 percent iron or more than U. percent. silica plus alumina.. The specifications for commercial manganese further required that the maximum particle size be 12 inches and that 75 percent of the product be coarser than 20-mesh. Therefore, fine material, such as table and flotation concentrates, had to be nodulized or sintered. In addition, carbonate manganese ores were not acceptable unless calcined.."

Aug 1, 1948

By D. Komljenovic, V. Kecojevic

Selection of the best possible truck type (model) is of crucial importance for the mine decision-makers. In this paper, authors contribute to the body of knowledge by developing a novel methodology for the selection of mining truck. Both the Coefficient of Technical Level (CTL) and Analytic Hierarchy Process (AHP) methods were used in this study. The CTL represents a mathematical function which takes into consideration the interrelations among the main technical parameters of mining trucks. The authors developed a hierarchical structure where both attribute categories and their importance, i.e. priority or weight in the selection process were determined. For each category, a number of sub-attributes and their priorities were assigned, and a pairwise comparison among them was performed using the AHP method. In the final part of the study, the CTL was integrated into the AHP and represents a holistic approach in the selection of mining trucks. A case study on 180 tonnes truck category offered by five manufacturers was carried out. A sensitivity study of obtained results was also performed indicating a very stable solution. The methodology presented in this paper may be used by mining operators to help in the selection of a specific type when acquiring a new truck. It may also be used by equipment manufacturers to help in analysis of potential benefits of envisaged modifications concerning an existing truck type and/or development of a new type.

Jan 1, 2007