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By J. L. Fuller

This paper contains a brief summary of design descriptions and generally accepted designations for longwall ventilation systems. Various ventilation systems for longwalls developed using single-entry and multiple-entry systems are discussed. Design considerations specific to longwall mining are included.

Jan 1, 1989

By J. C. Duchon

The U.S. Bureau of Mines is conducting human factors research for the purpose of reducing accidents and improving the person-machine interface found in surface and underground mining operations. Miners are exposed to a variety of environmental stressors, e.g., extreme heat, noise, vibration, and adverse illumination, throughout the workday. Exposure to these environmental stressors has been noted in the literature to affect performance on vigilance tasks. Since impaired performance at vigilance tasks can lead to industrial accidents, further investigation of the effects of environmental stressors on human performance is warranted. A brief description of the environmental conditions present in the mining workplace is followed by a review of experiments dealing with the effects of environmental stressors on vigilance task performance. The applicability of past research to actual mining operations is considered.

Jan 1, 1989

By Newell H. Orr

Titanium's performance characteristics in acidic oxidizing and mildly reducing environments make it applicable to numerous currently defined and many projected hydrometallurgical applications. With titanium's current and projected availability and price stability increased use in pressure leach, piping systems and electrorefining is practical.

Jan 1, 1983

By J. A. SINGMASTERN

THE New Jersey Zinc Co.'s vertical retort plants are believed to have been in continuous operation through the whole year. At Palmerton metal purer than that made from the same ore in the old plant has been produced and has been able to compete successfully with very pure electrolytic metal in die castings and other special uses where extreme purity is worth money. A new plant using this process was put in production by the Grasselli Chemical Co. at Meadowbrook, W. Va., early in the summer. It is said to be working very satisfactorily. It is understood that this plant will not produce high-grade metal. Two patents issued to Bunce and Mahler (Nos. 1,749,126 and 1,749,127) describe a method of operating the vertical retort so that practically lead-free metal can be obtained from ores containing consider- able lead. The zinc vapors and other gases leaving the reaction zone are filtered through a column of material maintained at a temperature high enough to prevent much zinc from condensing. The filtering medium is either periodically or continuously changed.

Jan 1, 1931

By A. G. Mayton

Bureau of Mines research has addressed improved operator protection for thin-seam shuttle cars. Because of working height restrictions in thin-seam mines (1.22 m or 48 in), MSHA regulations require that-canopy protection on shuttle cars be provided only in mines 1.07 m (42 in) and greater; however, variances are given to mines 1.22 m (48 in) and below. This paper reviews past Bureau efforts to develop protective structures for thin-seam shuttle car operators. The paper also discusses recent research leading to a novel method of protecting shuttle car operators, in mines as low as 1.02 m (40 in), through the use of a cross-car, end-mounted operator compartment.

Jan 1, 1989

David T. Day, Washington, D. C.: The paper of Mr. Adams is chiefly valuable because it emphasizes the ease with which petroleum can migrate in the earth's crust. Concerning this migration, I have little faith in the rôle of water as a carrier of gaseous or liquid hydrocarbon, suspended or mixed in the water in any way. My lack of faith is due to observation of

Jan 1, 1903

By Stephen Gerard Sawyer

This report presents a Fortran IV computer program for the structural analysis of space-frame protective canopies used in underground mines to protect equipment operators from falls of roof, face, or rib. This program entitled CANOPY permits rapid calculation of the elastic strength of a canopy for a variety of static loading conditions. Stresses in, and displacements of each structural member are computed and printed out. Additionally, identification of all members that have commenced yielding, weight of the canopy, total loads on the canopy, and maximum loads that the canopy can sustain elastically are output. Program description, input instructions, program listing, and two example problems are included.

Jan 1, 1972

By Takayuki Sakai, Takefumi Takuma, Lee Roesner

"70-foot deep rectangular-shaped bulkheads were built with sheet piles as launching and receiving shafts for a pipe jacking operation for new underground waterlines in a densely populated section of Los Angeles, California. The Press-in Piling Method was specified to drive 95-foot long sheets (a record for the method) to form the bulkheads for the Los Angeles Department of Water and Power’s LA-29 (DWP) Connection Modification and Pipe Jacking. The piling was chosen because of its very low noise and practically vibration-free nature since the site is surrounded by houses, an apartment complex, and existing water lines. The out front areas of the bulkheads were grouted to let the TBM go through without major ground water leaks. Hydrophilic foam grout was also injected in addition to welding steel scab plates on the inside to seal them to achieve sufficient watertightness behind a few split interlocks. BACKGROUND This project was located in the Crescent Heights area of Los Angeles which is a few miles south of Beverly Hills. The project represents the completion of the last phase of the Stone Hollywood Trunk Line. This was an 8-mile long water trunk line that averaged 60 inches in diameter and was built to improve the reliability of the DWP’s major water system. This section of the project involved driving 2 deep shafts to allow for the installation of a 350-foot-long 72-inch steel casing using microtunneling construction. See Figure 1 for the shaft locations and the tunnel alignment. The challenge for the project was that this water line would have to pass beneath the Hollyhills buried box drain (15 feet high by 20 feet wide). Further complicating the construction was the soils beneath the drain. The DWP chose to drive the tunnel at a depth of approximately 65 feet to ensure that the ground conditions were uniform and suitable for the microtunneling equipment. There were two previous attempts to construct this work which failed because of poor ground conditions and very high water levels. This third attempt was critical because the DWP could not afford to have another failure due to the fallout with the residents being impacted by the project."

Jan 1, 2016

By Joseph E. Pogue

NEW economic forces are at work in the petroleum industry.. In order to visualize these forces and clearly see their bearing on the producer, refiner and marketer, it is necessary to see in perspective the economic evolution of the business. For several decades prior to 1913 the outstanding feature of the petroleum industry was a trend toward integration, culminating in a huge combine, the Standard Oil Co. An important aspect of this integrative trend, however, was its concentration on the combination aid control of refining and marketing, leaving crude oil production, for the most part, to the exigencies. of small-unit competition. It is a noteworthy coincidence that during this era the law of oil and gas was formulated and applied, whereby these substances had to be reduced to possession to establish ownership; and the forces of competition in crude oil production were thereby intensified. It was to the interest of an industry, safeguarded in its control of manufacturing and markets, to have supply stimulated by legal convention as well as by individual initiative in order that the growing demand could be met without interruption. And so over-production of crude oil during this era was no handicap, but rather an aid, to the progress of the industry.

Jan 1, 1929

By William G. Christy

EFFORTS at smoke abatement date back to the year 1273 in England when a law was passed prohibiting the use of "sea cole." The law was not enforced, so King Edward I, 33 years later, appointed a commission "to enquire of all such who burnt sea cole in the city or parts adjoining, and to punish them for first offense with great fines and ransomes, and for the second offense to demolish their furnaces." Many other commissions have since been named to investigate the smoke problem in England, but it still persists in many British cities. In the United States the movement to abate the smoke nuisance started in certain Middle Western cities, and has made considerable progress. Until recently, the coal-producing industry co-operated little in smoke¬abatement programs, taking the attitude that smoke elimination is the dealer's or user's responsibility; and the dealers, in turn placed the responsibility entirely on the user.

Jan 1, 1942

Edwin A. SpeRry, Denver, Colo. (communication to the Secretary*) :—Since writing my former paper on this subject I have had several discussions concerning some of the statements contained therein, with men who have had a large experience with the old form of buddle, both in this country and in Cornwall. The present paper gives a brief statement of some of the points debated, together with the arguments and proofs in their substantiation. The first point is the question of the capacity. In my origi-

Jan 1, 1904

By E. M. Furness, A. S. Henderson

ORIGINALLY the Babbitt experimental plant grinding circuit consisted of one rod mill 10 ½ ft diam by 12 ft long in open circuit followed by two ball mills 10 ½ ft diam* 12 ft long in parallel circuit. Shortly after operations commenced it was apparent that the rod mill could not function satisfactorily at the required 125 gross tons of ore per hr. Attempts to operate at this rate produced: 1) excessive tramp material over rod mill trommel screen which could not be handled in this open circuit and 2) excess build-up of coarse ore in the ball mill circuits because of inadequate rod mill grinding. Since Reserve Mining Co. ore must be ground to 85 pct -325 mesh to produce a satisfactory iron concentrate, an efficient and controlled grinding circuit is highly important. The first step in trying to resolve this grinding problem was to determine which unit of the circuit was actually in trouble and to what extent. A series of tests conducted at a lower tonnage rate of rod mill feed indicated that one ball mill could grind satisfactorily at rates up to 70 gross tons of rod mill feed per hr.

Jan 12, 1957

By Ron H. Derammelaere

Coal Slurry Test Pipeline and First Recorded Commercial Pipeline Wallace Andrews founder of New York Steam Company awarded patent for ?Method of Transportation? that involved pumping finely divided coal in slurry form built test facility at Madison Avenue and East 58th Street in New York City died in 1899 in a fire and coal pipeline work was not continued First recorded commercial coal slurry pipeline designed by Gilbert Bell in 1914 to move coal from barges on the Thames River in London to a powerhouse in 8? tubes (660 yards long)

May 1, 2013

By S. McTavish

Since mechanically suitable grinding mills were available in 1908, mill operators have been searching for the best material and design with which to line the mills. These liner systems had to fulfill several criteria. First and foremost they had to last long enough in an operating mill to protect the mill structure from the abrasive wear of the ore and the grinding media. In addition they had to be able to efficiently transfer the energy from the mill to the mill charge in order to facilitate the grinding process. The liners also had to be easily attached to the mill when new and removed from the mill when worn out. The first liners used were generally made of cast white iron, Hadfield manganese, unalloyed high carbon steel and composites of steel and concrete or cemented in flint blocks or natural stone. 1

Jan 1, 1989

By Paul Richardson

This paper discusses the drilling techniques and equipment used by Loffland Brothers Company to drill the AEC's UC-3 large diameter shaft in Nevada. Included are pictures and illustrations of the drilling-mud circulating system, the surface and downhole drill-string and the special heavy-duty mast and hoisting equipment required to do the job. The purpose and method of lining the large diameter holes along with the technique and materials used to backfill the lining to hole annulus are discussed briefly. Areas requiring improvement in both equipment design and technology for large diameter shaft drilling are discussed briefly. Shafts as large as 140 inches in diameter to depths of 5,000 feet can be drilled with existing equipment and technology.

Jan 1, 1969

By Frances H. Clark

DEVELOPMENTS in powder metallurgy have been disappointing in 1943. If any new part has gone into large-scale production, knowledge of it has been restricted by considerations of national security. Nor have any outstanding papers appeared to advance the theory of the subject during this period.

Jan 1, 1944

By R. V. Ramani, C. B. Manula, A. Owili-Eger

This report was prepared by The Pennsylvania State University under USBM Contract No. G0111808. The contract was initiated under the Coal Mine Health and Safety Program. It was administered under the technical direction of DMRC, with Mr. G. R. Schottler acting as the technical project officer. Mr. J. A. Herickes was the contract administrator for the Bureau of Mines. These applications were developed initially as a part of the instructional material for the course Mng 422, "Mine Ventilation and Air Conditioning" at the Department of Mineral Engineering, The Pennsylvania State University. This ventilation simulator was developed under contract from the Department of Environmental Resources, formerly the Department of Mines and Mineral Industries, Commonwealth of Pennsylvania.

Jan 1, 1975

By Frederick Laist

ABOUT six years ago the Anaconda Copper Mining Co. decided to investigate the possibility of extracting zinc from the ores of certain mines in the Butte district. These ores are of a complex character and contain so much iron and lead that the concentrate contains only 33 to 35 per cent. zinc. Investigations showed that while a high-grade concentrate could not be obtained by ordinary methods, such as tabling and magnetic treatment, a fair grade could be made by the Horwood process. In this method, the concentrate resulting from the flotation of all of the sulfides is given a light roast and this calcine is subjected to flotation in the presence of a large amount of sulfuric acid; the resulting concentrate contains most of the zinc and a residue contains most of the iron. The fact that the lead, copper, and silver are divided approximately equally between the zinc concentrate and the iron residue and the large consumption of acid, which ranged from 50 to 100 lb. (22 to 45 kg.) per ton of concentrates, were serious objections to this plan. The zinc recovery, moreover, was low, as a considerable percentage invariably accompanied the iron. While a profit might be made on the ores by the use of this process, it was thought that other and more promising methods might be devised. After carefully studying the field and doing some laboratory work on various processes that had been suggested, it was decided that the electrolysis of sulfate solutions was the most promising. We soon found, as have other investigators, that the only way to obtain a good zinc deposit is to have the electrolyte free from all metals more electro-negative than zinc, such as copper, cadmium, lead, arsenic, antimony, etc. Arsenic and antimony are particularly injurious, causing very poor current efficiency and small yield per horsepower when present in amounts so small as almost to defy detection-1 mg. or less per liter.

Jan 10, 1920

By W. B. Plank, A. C. Callen

WAR and normalcy do not walk hand in hand, whether it be in industry, the educational field, or in the daily lives of individuals. Schools and departments offering curricula in mineral engineering have been seriously disrupted, beginning with 1942 and reaching a low during 1944. Selective Service regulations and voluntary enlistments have effectually stopped the flow of college-trained men into the mineral industry, and the flow into the colleges is little more than a dribble. The year just closed has been a most serious one for our institutions. Until March many of our faculties had been kept reasonably intact because of the large training programs of the Army and Navy. Although the number of

Jan 1, 1945

By J F. Costa, A Grigorieff

Coal mining reclamation is a worldwide concern. This paper presents a Brazilian example where the economic aspects of reclamation are considered. The basic goal of the study is to transform the reclamation procedures into an economic process by integrating the use of land after reclamation and developing profitable post operations. Some of the activities considered in this case study include: using of the coal pit as a landfill, considering appropriate landfill design and construction; using the area for forest development; and developing grassland, forests of native species and the construction of ponds for fishery. This study will conclude that the mined area is: capable of storing large quantities of waste at a competitive cost and at a low environmental risk; commercial forest development is economically feasible; and the lakes and other reclaimed areas can be integrated into the landscape creating a fresh water supply and an area to raise cattle.

Jan 1, 2005