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By Richard D. Mehring

A refined ad improved self-sealing brattice for use in coal mine rescue and recovery operations for directing the flow of air has been developed and tested by Goodyear Aerospace Corporation for the U.S. Bureau of Mines. The brattice is made from a lightweight, low cost material that meets MSHA flammability requirements. The units can be erected using pins, spade or lightweight extensible poles. Tests here conducted to determine leakage rate from minimal to a maximum of 1.5" H20. The ability to handle reverse flows was demonstrated and a non-flammable foam was used as an auxiliary sealing agent.

Jan 1, 1978

By Kevin Saeler, Patrick Willaman

Utilizing automation is one way to improve competitiveness. Roof and rib bolting in underground coal mines has not changed significantly for more than 40 years. Most roof bolting is still a largely manual process involving high levels of staff carrying out repetitive work. Roof bolting statistically has one of the highest levels of underground accidents, including finger, hand, and arm injuries. Operators are exposed to falling objects and becoming entangled in roof bolting apparatus while roughly moving awkward 6-ft drill steels and roof bolts. It is estimated that over 25 million roof bolts are installed annually in the U.S. underground coal market with well over 1,500 operators involved in roof bolting on a day-to-day basis. Recently electrohydraulic roof bolting rigs have been installed to offer partial automation of the drilling cycle and the bolting cycle. The next stage is to provide a storage and loading system to allow full automation of fullcolumn resin roof bolts. This paper reviews the latest electrohydraulic roof bolting equipment and discusses the testing of a fully automated drill rig. Full electronic control allows each step of the roof bolting process to be recorded, providing a digital record of each installation, including hole depth, spin time, gel time, torque, and cycle time. Other benefits include monitoring of water pressure and flow, used to prevent blocked drill steels as well as digital fault finding. A fully automated roof bolting machine greatly improves operator safety and gives high-quality repeatable roof bolting with reduced cycle times.

Jul 1, 2023

By BUREAU OF MINES

This summary of State laws on explosives was compiled primarily to ascertain what subjects relating to their control have been acted upon by each State legislature and , in general , how they have been treated . It does not include any legislation passed after 1942 , or any proclamations , regulations , or administrative orders . It does not purport or attempt to be authoritative . If any problem arises involving interpretation of the statutes of any particular State , the original source must be consulted for the exact words used by the legislature . This summary , however , will be useful in determining whether relevant statutes exist , and in locating thern quickly, with a minimum of effort . It will be of value also in comparing statutes in one State with similar statutes in other States to determine what construction has been placed upon them by the courts of these jurisdictions or to contrast the varying provisions of many States upon a similar subject . To make these comparisons easier , the statutory provisions for each State have been grouped under several major topics in outline form . Although this sometimes has resulted in disruption of the continuity of individual acts , the increased general clarity and availability of comparable sections have more than justified the procedure followed ,

Jul 1, 1943

"INTRODUCTION Industrial utilization of the present submarginal domestic manganese resources of the United States is wholely dependent at this time on the electrolytic manganese process established as the result of 4 years of continuous operation of the Bureau of Mines pilot plant at Boulder City and 7 years' operations of the Electro Manganese Corporation commercial plant at Knoxville, Tenn.Three Kids ore provided the feed for the Boulder City pilot plant during 3 years of operation. Hence, the electrowinning characteristics of the ore have been thoroughly established, making possible accurate estimates for commercial operations.Before the Defense Plant Corporation constructed the leaching plant, the Bureau of Mines conducted an exploration project to determine the extent and grade of the ore reserves. Additional exploration, development, and mining by the Manganese Ore Cc, have accurately determined the tonnage and grade of ore. A large tonnage of stock piled ore is now available for immediate processing, and a considerable tonnage of openpit ore has been stripped of overburden preparatory to mining. Numerous facilities, such as power, water, and housing, needed for an electrolytic manganese plant are already available.All of these factors, as well as plans for installation of scale electrolytic manganese plant facilities, are presented in detail in the chapter entitled, ""Mining and. Electrolytic Reduction of use from Three Kids Manganese Mine."" The Manganese Ore Co. kindly provided information on the present ore reserves and state of development of the mine."

Jun 1, 1945

By James A. Wasson

Because of the danger to life and property in a coal mine if an oil or natural gas well should be accidentally intersected during mining operations, certain precautionary measures should be carried out prior to entering previously unmined areas. The locations of all wells both at the surface and at the depth of the coalbed should be accurately determined. The condition of the well should be learned from surface observations, and more importantly, from subsurface examination by geophysical logging devices where possible. It is also desirable to learn the physical properties of the hydrocarbon-bearing rock formation and the hydrocarbon fluids. The major hazard presented by oil or natural gas wells to mining operations is that of explosion and fire due to the rapid release of gas into the mine atmosphere. Wellbore pressure, the principal index of danger, should be determined by one or more of the methods described and by a service company such as those listed in the appendix. Because of high pressures involved and the consequent hazard, much emphasis has been placed on underground storage of natural gas in areas containing minable coalbeds. Maps are shown of the principal coal producing areas and the locations of currently active gas storage reservoirs. A checklist has been included of factors to be considered when mining coal in an area where oil or gas wells exist.

Jan 1, 1973

By B. C. Alberts

Planning the use of South Africa's energy resources, especially coal, is of the utmost importance. The State and the mining industry require reliable official estimates of the economically mineable coal reserves for planning purposes. An overview of al the previous reserve estimates is given, with specific attention to the two most recent estimates-those of Petrick and De Jager. The differences between these two estimates are highlighted. The following important aspects are discussed: . the need to update the information regarding South Africa's mineable coal reserves, . the necessity of understanding and agreement between the coal-mining industry and the State department responsible for updating the coal-reserve data, and . the importance of the specific assumptions used in the updating of the data. A downward adjustment of mineable reserve figures is proposed, and the factors that influence the meaningful exploitation of the coal reserves are discussed. A recommendation is made as to how the Waterberg coal reserve should be exploited, and it is concluded that the Soutpansberg Coalfield cannot be exploited economically in the foreseeable future. An evaluation of the status of the coal-export trade is made and compared with the assumptions and targets set at the start of the coal-exportation scheme. The comparison shows the extent to which the exploitation of the coal reserves is being negatively influenced by the current market situation. Recommendations are made regarding planning for the coal-export market, and the aspects that have to be taken into account to keep South Africa in the export market are identified. Reference is made to the fact that the present unrestrained wage and salary adjustments, which show a total disregard of South Africa's poor productivity record, require serious thought and speedy rectification if the country is to survive in the export market. A salary and wage strategy must be developed to suit the specific needs of the Republic of South Africa.

Jan 1, 1987

By Ronald Erdmann

Today the BOF filter dusts and sludges are mainly dumped due to their zinc contents. By typically ranging from 2 to 5 % they prevent the filter dusts and sludges from beeing recycled via the blast furnace route. Based on the different discharge kinetics of Iron and zinc during the main blowing period In a bottom stirred BOF a simple and efficient system for recovery allow zinc fractions has been developed. The obtained material Is suitable for recycling without nsc of shell formation In the blast furnace. Different subsequent development steps have been performed. By starling with a very simple lime dependent model the sludge from the BOF off gas cleaning system was collected in two different sludge channel systems. This model based an the fact that most of the scrap based zinc Is discharged from the melt within the first eight to ten minutes of the BOF process. To Improve the system a spectroscope zinc sensor was Installed at the hot section of the off gas cleaning system to get more reliable informations on the actual zinc concentation of the BOF dust. By use of the system up to 50 % of the BOF sludge can be recycled.

Jan 1, 1995

By B. Samanta

LHD (load haul dumper) is now used as a loading machine for intermediate mechanization in underground coal mining. For survival in the intense competition in the global business environment in recent years it is essential that LHD machine should be reliable and maintained effectively and efficiently. This paper seeks to study the reliability, availability and maintainability (RAM)of an LHD machine with failure and repair data by Markov modelling. The constraints and reasons for machine unavailability are outlined. The reliability and maintainability of an LHD and its subsystems are evaluated. Possible modification or design alternatives are highlighted. Reliability and maintainability of an LHD system are disappointing. There is room to take decisions on optimal maintenance planning and machine improvement from this analysis. Keywords: reliability, availability, maintainability, Markov model, LHD

Jan 1, 2004

By T. Gerritsen, R. MacRosty, R. Pula, P. Gebski, W. L. Ying

Furnace run-outs can cause extended furnace downtime for repair, while leaks or more severe failures in the cooling system can lead to brick hydration or in severe cases, steam explosions. These incidents can result in lost production, damage to equipment, injuries and casualties. To prevent such incidents, reliable and accurate techniques to monitor the critical components of the furnace such as refractory lining, furnace structure, taphole integrity and main water circuits are required. This paper describes several advanced methods that have been developed to assess the condition of furnace integrity, refractory lining, tapholes and cooling water circuits.

Jan 1, 2015

By A. Noël, R. Lapierre, M. Provencher

"Modem aluminum smelters are facing significant operating cost pressure. Key methods used by smelters to manage this pressure are automation and production-information systems to optimize processes, manage quality, anticipate problems and reduce operating costs. In 2002, Aluminerie Alouette Inc. began its Phase II Expansion project, and retained the joint venture of SNC-Lavalin and Hatch (SLH) as its engineering, procurement and construction management (EPCM) team. Alouette had the distinction of being one of the most efficient aluminum smelters in the world. Alouette already understood the importance of systems integration in project delivery. For Phase II, key objectives were identified to ensure ""a state of the art"" integrated architecture that would support Alouette's production goals to integrate the existing facilities with the expansion, to form a single efficient facility and meet project schedule and budget targets. Achieving those objectives within the context of a large project often creates major challenges due to the nature of the traditional EPCM delivery model, which relies on several vendors and third-party-systems integrators. In this case, an integrated Alouette-SLH team was made responsible for all aspects of the systems integration, taking over the task from most suppliers. The integrated team was responsible for delivering an automation system and plant-wide-production IT system for the new facilities while accommodating migration for the existing systems. Through the use of rigorous methodology and advanced state of the art technology, the IT and automation strategy led to significant value creation and is recognized today as one of the key factors of the project's success. The primary results were: fast and efficient start-up of facilities, due to quality programming and implementation; a plant able to operate as a single entity; automation and IT systems delivered before time and under budget; standard programming methods implemented throughout the plant; and reduced and simplified maintenance."

Jan 1, 2006

By R. A. Hill

A brief explanation of the theoretical functioning of a regenerative system followed by its application to firstly, shuttlecars and then continuous miners and its effect on performance thereof with regard to handling, production and safety.

Jan 1, 1986

By E. B. Wilson

"Although the Operations Research technique of Reliability Theory has been applied with marked success in many fields, including the Apollo spaceship programs, the concept of reliability has not been generally adopted in mining and other heavy industries. Of course, reliability, or the probability that a system will be able to operate without a failure for a given interval of time, does not require the same emphasis in mining as in the aerospace industries. Nevertheless, certain aspects of Reliability Theory can be followed advantageously. For example, reliability calculations can determine the best time to overhaul and whether to retain stand-by units.The usefulness of the pseudo-operations research technique known as Replacement Theory is more readily re-cognized by the maintenance engineers in mining and other heavy industries. One of the least complex models enables the optimum Lifetime of an asset to be determined."

Jan 1, 1970

By A. G. Roach

HISTORY AND LOCATION SEAL HARBOR GOLD MINES, LIMITED, was incorporated in January, 1934, to take over 116 acres of mining lands in the Stormont gold district, Guysboro county, Nova Scotia. The nearby ten-stamp Mulgrave mill was also purchased, and since that time 974 acres of adjoining properties have been secured from the Government by direct lease. The property is served by a motor road and is about two miles from the village of Goldboro, situated on the shore of Isaac's harbour. The bulk of ?the supplies are brought in by coastal steamer from Halifax, a distance of about 100 miles, since the nearest railway connections are at Antigonish, some 40 miles distant. EARLYY WORK The Seal Harbor properties include the old Partington and Beaver Hat mines. A small tonnage of ore was mined from each and treated on the properties in stamp mills, which were later torn. down . A survey of old records shows that this ore averaged about $8.00 gold per ton. Development work by the present Company was confined to the 100-foot level until February, 1935, but after that rime the incline shaft was deepened to 425 feet and the 300-foot level was explored east and west of the shaft. Six belts of ore were intersected to the west of the shaft. The ore from these belts was hand sorted and the ore portion was put through the 10-stamp Mulgrave mill to defray operating expenses and to serve as a sample of the deposits. The average recovery per ton from this sorted ore was $6.10. Samples of the ore were sent to the testing laboratories of the Mines Branch, at Ottawa, and of Canadian Industries, Limited, at Toronto. Recommendations from both of these authorities were for removal of the coarse gold by concentration and barrel amalgamation, followed by cyanidation of the residue.

Jan 1, 1937

By Bruce D. Hebb, Shahin Shadlou

Fiber Reinforced Polymer (FRP) is an excellent material choice for a broad spectrum of corrosive fluids and, in many cases, offers the best value per dollar. FRP Flanges present the greatest design challenge of all standard piping components. The theory underlying the design of flanges is very complex. In addition, due to the nature of FRP material, proper fabrication of the flanges is as critical as the design. In this review, the challenges of making FRP flanges along with the design techniques and best practices of fabrication that will lead to a high-quality flange will be discussed.

Feb 1, 2024

By Art Hamid, Manfred Wong, Carlos Jaramillo, Greg Raines, John Caulfield

"The Central Bayside System Improvement Project (CBSIP) is a critical element of the Sewer System Im-provement Program (SSIP), a 20-year, $6.9-billion investment by the San Francisco Public Utilities Commis-sion (SFPUC) to upgrade San Francisco’s 100+ years old seismically vulnerable combined sewer system. The CBSIP’s centerpiece, a proposed 10,000-foot-long (3,048-meter-long) Channel Tunnel, will provide reliable and redundant gravity conveyance and storage of combined wastewater flows from the northern and central parts of San Francisco to the Southeast Water Pollution Control Plant (SEP) while ensuring compliance with regulatory requirements for combined sewer discharges to the Bay. A tunnel with a diameter of 23 to 30 feet (7 to 9 meter) is being planned using pressurized-face tunnel boring machine technology. Project challenges include tunneling through Franciscan Bedrock, mixed ground conditions in close proximity to the Bay, connector tunnels and shafts, construction in congested urban environment, and challenging real estate issues for shaft access. BACKGROUND AND NEED FOR TUNNEL The City of San Francisco is one of the most beautiful cities in the world. About 850,000 people live in the city and many more come to work, for tourism, and for attending conferences. The SFPUC is a department of the City and County of San Francisco that provides energy, drinking water and wastewater services to San Francisco, wholesale water to three Bay Area counties, and green hydro-electrical and solar power to San Francisco municipal departments. The SFPUC wastewater system includes tunnels, large storage/transport boxes, 1000 miles of collection sewers, 28 pump stations, and three wastewater treatment plants. San Francisco’s combined sewer system collects both wastewater and stormwater in the same sewers, which is then pumped, treated to stringent state standards and discharged into the San Francisco Bay and Pacific Ocean. After decades of service, much of the sewer system is nearing end of its working life. During the 1989 Loma Prieta earthquake, damage to SFPUC water and wastewater infrastructure was extensive. The 11,200-foot-long (3,400-meter-long), 66-inch-diameter (1,676-mm-diameter) Channel Force Main, built in 1976, and a critical component of the SF wastewater system was also damaged. This force main carries 70 percent of the bayside dry weather sewage flow from the northern and central part of the city to the SEP. The force main is at the end of its life and was not constructed to the current seismic code; in addition it has no redundancy. Figure 1 shows the project background and the force main that will be provided redundancy by the new gravity tunnel."

Jan 1, 2016

BHP Hartley Platinum operates an electric smelting furnace to treat Cu-Ni-PGM concentrate at its plant in Selous, Zimbabwe. The furnace, originally built by others, has experienced problems including severe refractory erosion of the sidewall. Hatch Associates has designed several important improvements to the furnace, including: ? water-cooled copper cooling elements in the slag zone ?air-cooled copper cooling fins at the metal level ?water-cooled copper tapholes ?binding system providing vertical refractory compression ?electrode seals ?new feed pipes Novel construction techniques employed on this project to reduce shutdown duration are discussed.

Jan 1, 1999

By A. L. Service, C. C. Popoff

Phosphate deposits in Montana , Idaho , Wyoming , and Utah are important factors in the mineral , agricultural , and industrial economy in the western part of the Nation . This report presents background information , including geology , mining , beneficiation , processing , resources , and economics , assembled to provide a comprehensive introduction to a series of four area reports . About 20 percent of the Nation's phosphate is produced from the Western field where there were 6 surface and 9 underground mines in operation in 1963 . This region also has an estimated 58 percent of the Nation's phosphate reserves , and continuing development is assured by these abundant resources and an increasing demand for phosphate products . Long range forecasts indicate that the United States will continue to use increasing amounts of both agricultural and industrial phosphate products . Beneficiation has become an important part of the phosphate processing industry , and two flotation plants and several washing plants were in operation in 1963. Recent studies by the Bureau of Mines Metallurgy Research Center , Albany , Oreg . , have been directed toward developing flotation processes applicable to treatment of marginal phosphate rock . Other Bureau of Mines research is being directed toward improved methods of ore recovery , ground control , and mining .

Jan 1, 1964

By Pedro Lilienfeld

This report describes a program whose objective was to develop, design, fabricate and laboratory-test two prototype instruments capable of real-time selective detection and measurement of airborne fibrous-shaped particles. The operation of this fibrous aerosol monitor (FAM) is based on the rotation imparted to the acicular particles by means of a rotating quadrupole electric field of the order of 3000 V/cm. This field induces a dipole charge separation on the fibers and aligns them with the applied field. The selective detection of the fibers is effected by synchronous detection of the resulting modulation of the light scattered from a continuous-wave helium-neon laser beam by the rotating particles. The theory of operation, design of the electric-optical detection configuration and the electronic signal processing method are discussed. By means of a scattering pulse sharpness discrimination technique, fibers whose length exceed a selectable value are detected and their number concentration digitally displayed. Counting times of 1 to 1000 minutes permit the measurement of fiber concentrations between 0.001 and about 30 cm-3. A concentration of the order of one fiber per cubic centimeter can be assessed within a relative standard deviation of 10 percent with a counting period of 10 minutes. The FAM is a portable, battery-powered instrument capable of operating continuously for about 4 hours between battery charges. Preliminary tests with crocidolite and crysotile asbestos as well as with glass fibers were performed in the laboratory and the results indicate good correlation with the standard NIOSH phase contrast microscopy filter counting method.

Jan 1, 1977

By H. Foster Bain

Steel for any large structure must be imported, the Hanyang works being entirely unable to supply local demand. The United States Steel Products Co. has warehouses and small stocks at Shanghai and at normal times there are heavy importations from Europe. It is difficult to obtain any accurate index of prices, but comparison of customs valuations with Pittsburgh quotations shows angles, bars and plates to have averaged $10 gold per ton higher in China in 1914, while on galvanized and tinned plates the excess was- $38 per ton. The margin since has been greater. Previous to the war little machinery was manufactured in China. There were shipyards at Shanghai and at Hong Kong which built a small number of engines, and small foundry and repair works are found at a number of ports. Their capacity was limited and the difficulties and delays incident to transport in China so numerous that in practice every important mine has a small foundry, boiler works, and machine shop. This must be taken into account in plans for work in the country. While skilled workmen can be found it is to be noted that most of them have been trained

Jan 1, 1921

By T. Lane Carter

(Canal Zone Meeting , October , 1910.) INTRODUCTION. IT is a curious fact that while in our Transactions there are papers dealing with mining-districts in all parts of the world, in Europe, Asia, Africa, and Australia, there is not one which describes the mining possibilities of Nicaragua; our near neighbor. To be most interested in distant objects, like the moon, .and to neglect what lies at our feet, appears to be a trait of human nature. The neglect of Nicaragua is not confined to the American Institute of Mining Engineers. In no other transactions am I :able to find papers dealing with mining in Nicaragua, some parts of which are as much in need of discovery and research as the North Pole.. I hope this paper will be the precursor of many others to be printed in our Transactions, dealing not only with the mining possibilities of Nicaragua, but with the whole of Central America, where there are vast areas awaiting skill and capital for their development. Much of this capital and skill should come from the United States in the future, although it is probable that European capitalists, when they appreciate fully the possibilities, will investigate more and more the mining-resources of Nicaragua and other Central American republics. Fig. 1 is a sketch-map of Nicaragua showing the principal mining-districts. II. HISTORY. Mining in Nicaragua did not begin yesterday. It was commenced by civilized man when the Spanish conquerors penetrated into the interior and forced the natives to procure the precious metal for them. It is strange that the Spaniards did not find more gold, and work on a scale as extensive as in Colombia and other parts of South America. Probably in Nicaragua the Indians covered up most of the rich prospects

Dec 1, 1910