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By E. T. Turkdogan, P. Grieveson

Experimental results are presented for the rate of solution of nitrogen in a iron in the temperature range 750° to 873°C and in 6 iron in the temperature range 1410° to 1470°C. It is shown that the rate controlling process is diffusion of nitrogen into the iron. The diffusiting of nitrogen in a and 6 iron is derived from the results, and the temperature dependence of the diffusivity is represented by the equation D = 7.8 x e- 18,900/RT sq cm per sec. The solubility of nitrogen in a and 6 iron, in equilibrium with 1 atm pressure of nitrogen, has been measured. Using these results and other available data, it is found that the variation of the logarithm of nitrogen solubility with the reciprocal of absolute temperature is nonlinear. In an Appendix, some results of Darken and Smith are presented for the rate of solution of nitrogen in iron using ammonia + hyidrogen mixtures. These data also support the view that diffudsion of nitrogen in iron is the rate-controlling process when ammonia + hydrogen mixtures are used. A considerable effort has been made to obtain data on the solubility1-5 and diffusivity of nitrogen in a iron6-l2 because an understanding of the effect of nitrogen on the properties of steel must be based on an accurate knowledge of the properties of nitrogen in pure iron. However, no information is available concerning the kinetics of solution of nitrogen in a and 6 iron. Recently the authors13 have investigated the rate-controlling mechanism operating in the kinetics of solution of nitrogen in y iron. This study was directed to determine the rate-controlling processes for similar reactions with a and 6 iron as well as to establish values for the solubility of nitrogen in equilibrium with nitrogen gas in a and a iron. EXPERIMENTAL The procedure used in experiments to determine the rate of solution in cylindrical iron rods was the same as that described in a previous communication.13 Ferrovac E grade iron used in all experiments contained the following impurities in weight percent: C, 0.005; Mn, 0.001; P, 0.002; S, 0.006; Si, 0.006; Ni, 0.025; Cr, 0.002; V, 0.004; W, 0.02; Mo, 0.01; Cu, 0.001; Co, 0.01; 0, 0.007. After cleaning the surface, the iron rods were treated in an atmosphere of purified hydrogen for 17 hr before the reacting gas was introduced for known experimental times. After quenching, the samples were sectioned radially and analyzed for nitrogen. In addition to experiments using rods, iron foils were used in the measurements of solution rates of nitrogen in a iron. The foils of two different thicknesses were prepared by cold rolling Ferrovac E grade iron cylindrical rod to 0.051 and 0.152 cm. Foil samples were used in a rectangular form 5 cm long and 1.25 cm wide. The specimens were thoroughly cleaned of surface oxide with fine emery cloth and degreased with carbon tetrachloride immediately before entry into the furnace. The experimental procedure was the same as that used in the study with rods. At the completion of an experiment, the foil samples of the nitrogenized iron were analyzed for nitrogen after discarding 0.3 cm from the perimeter of the specimen. Iron foils were nitrogenized and denitrogenized in the a and 6 range with a gas mixture of 95 pct N and 5 pct H for times varying from 5 min to 2 hr. Results obtained for the average composition of nitrogen in iron for these experiments are presented in Fig. 1. Prior to the denitrogenization experiments, the samples were saturated with nitrogen at 1000°C and 0.67 atm N, giving a uniform nitrogen concentration of 0.0204 pct. According to the known a-y phase boundary in the Fe-N system,14 this composition lies within the ferrite region at temperatures 750" to 850°C. Use of this initial nitrogen content insured that reaction occurred between the gas and a single solid phase, a iron. Examples of the results for the mean concentrations of nitrogen in cylindrical iron rods, 0.356 cm radius for both the a and 6 ranges are given in Fig. 2. Typical examples of the results obtained for the radial distributions of nitrogen in rods are presented in Fig. 3. It appears that the results for radial distributions can be extrapolated to constant surface compositions which agree with the equi-

Jan 1, 1964

The Annual Business Meeting of the members of The Rocky Mountain Coal Mining Institute held during the 83rd Regular Meeting of the Institute was called to order by the president, Bernard Bernstrom at 2:50 p.m. Tuesday, June 30, 1987 in the Janss Auditorium of the Snowmass Conference Center in Snowmass Village, Colorado. Thirty-one were present and a quorum was established. The president outlined the purpose of the meeting was to inform the members of the status of the affairs and activities of the corporation during the preceding year. It was moved by Leon Jeannot, seconded and carried to approve the minutes as published in the 1986 Proceedings. The chair called for reports of the various committees and these reports will by placed on file in the RMCMI Office. Bylaws and Resolutions. Chairman Loren V. Linville reported there were no bylaws revisions. He further reported that the Board had adopted three resolutions: (1) Noting the passing of members since the last convention-Benton Boyd, E. A. Hare, E. S. Moran, Jr. and Edward Prostel. (2) Of appreciation to the Executive Secretary, officers, chairman, Diamond Jubilee chairman and committees and convention committees for an outstanding job in preparing for the 83rd Regular Meeting of the Institute. (3) To recommend to all RMCMI members that, on an individual basis, they each oppose replacing coal fired generation with natural gas generation. Membership. Chairman Leon Jeannot reported that at the beginning of the 1986 fiscal year, there were 881 active or dues-paying members. During the year, 219 members were dropped for a variety of reasons such as non-payment of dues, transfer, employed elsewhere, change of address. Ninety-six new members have been recruited for an active total of 758. In addition there are 55 Life Members, 20 senior members, six scholarship winners and seven supporters for a net total of 846. The budget of RMCMI calls for 1,000 active members and we must address and plan for those short-term prospects as they will certainly impact our membership. A full report is on file in the RMCMI office. Patrons of the Institute. Chairman Ira McKeever reported that only 59 Patrons renewed their support during 1986-87. Program. Chairman Bill Balaz announced that the convention program theme "This is OUR Life", as presented in "Past", "Present" and "Future" segments was very well received. He called for additional helpers another year and suggested that next year's program format be changed to a hard hitting one. Publicity. Chairman Tom Egan reported that of the three newsletters sent members during the year, that the most effective one was the newspaper format one and recommended its use next year. RMCMI hired Bob Jacob who heads his own public relations firm to solicit advertising for the Proceedings on a contract/ commission basis. He attended the convention for this purpose and to solicit business card ads. A full report is on file in the RMCMI office. Scholarship. Chairman Keith McGinnis reported that five of the six scholarship recipients were present at the convention. Each was introduced to the membership at the Tuesday morning Scholarship Breakfast, presented a plaque and responded. The input from each winner was most favorable to the program. Each was appreciative of the many contacts made and the educational seminars and programs. The selection process started in March and was completed in May, except for one university which had difficulty in providing a candidate. It is suggested that the initial contact with the institutions be made in December and completed by April 1. This year, for the first time, three of the six universities were visited for the purpose of interviewing the candidates. They were Colorado, Utah and Wyoming. A very positive feedback was received from these schools and it is recommended that the practice continue. CONVENTION COMMITTEES Convention Arrangements. Doris Finnie presented the following report: As a professional meeting planner, this Diamond Jubilee convention was indeed a great challenge. One meal was added to the package and thus increased the individual cost. Snowmass Resort Association is unique in that they utilize a conference coordinator who acts as the middle man between myself and the usual persons we deal with, like AV personnel, the chef, the banquet director, the steak fry personnel, the Sunday tour etc. so the office had to become creative. For instance, we learned early on we could not deal with the local florists. It cost us lots less to buy our flowers wholesale in Denver, have my husband drive them up and our West Virginia daughter to arrange them! But, finally her floral arrangement class at CSU paid off! This was truly a Finnie family orchestrated convention. Our Lakewood daughter acted as Scholar-

Jan 1, 1987

Columbia University, School of Mines, New York, N. Y. For many years the School of Mines published a Quarterly containing many valuable papers on mining, geology and kindred subjects, but the publication has been discontinued for several years and copies are no longer available for general distribution Papers by members of the staff are now sent to the various scientific societies, and only longer works are published by the Columbia University Press Publications of the Columbia University Press deal almost wholly with subjects other than geology and mining but one may be mentioned: Regulating an industry, by A. H. Stockder. An account of the experience of the Germans in attempting to regulate the Rhenish-Westphalian Coal Syndicate in 1893 to 1899; $2.50. For a list of publications, address the Columbia University Press at the above address.

Jan 1, 1933

By Bahrein Petroleum Company

In Comodoro Rivadavia, well 8. 132, drilled in zone No. 2, has discovered between 5205 and 5297 ft., the dcepest pool yct found in this field. The oil production in Bahrein for the year 1939 totaled 7,588,554 bbl., a decline of 709,444 bbl. from the 1939 production of 8,297,998 bbl. The production for the first seven months of 1939 remained fairly constant, the daily average by months during this period ranging between 20,000 and 22,000 bbl. per day. The daily average rose in August to the year's high of 23,800 bbl. per day, then dropped gradually to the year's low of 18,787 bbl. per day for November. The daily average for the year was 20,791 bbl. At the end of 1939 there were 59 wells producing and 8 wells drilling.

Jan 1, 1940

By Bahrein Petroleum Company

In Comodoro Rivadavia, well 8. 132, drilled in zone No. 2, has discovered between 5205 and 5297 ft., the dcepest pool yct found in this field. The oil production in Bahrein for the year 1939 totaled 7,588,554 bbl., a decline of 709,444 bbl. from the 1939 production of 8,297,998 bbl. The production for the first seven months of 1939 remained fairly constant, the daily average by months during this period ranging between 20,000 and 22,000 bbl. per day. The daily average rose in August to the year's high of 23,800 bbl. per day, then dropped gradually to the year's low of 18,787 bbl. per day for November. The daily average for the year was 20,791 bbl. At the end of 1939 there were 59 wells producing and 8 wells drilling.

Jan 1, 1940

By J Morton

There are many avenues for potential liability facing the Mining Industry today. Liability for breaches of environmental statutes such as the Resource Management Act 1991 and the Hazardous Substances and New Organisms Act 1997 include not only financial penalties but imprisonment and perhaps even more significantly will affect the reputation of the Industry. The potential for liability is not restricted to the employees that cause the actÆs to which liability attaches, but also potentially affects all the levels of management and even the company itself. There is also potential for liability through common law actions which can be utilised in cases of environmental harm. These should not be ignored by the Mining Industry. The Mining Industry must take a proactive approach to minimise exposure to potential environmental liability. This can be achieved by undertaking comprehensive environmental management initiatives and policies.

Jan 1, 2005

By T. Takahashi, K. Oyamada, Y. Miyata, T. Isoo

The carbonation reaction of steelmaking slag has been known for many years. However, the size of blocks manufactured from this by-product material has been limited due to the difficulty of achieving a uniform reaction throughout the block. Using newly developed conditions, large porous slag blocks (1.0 x 1.0 x 0.5 m) were produced by car¬bonation of steelmaking slag with the optimum amount of water and supplying CO2 deep into slag powder compacted in molds. The development of these blocks has great poten-tial to solve the problem of slag utilization, for example, by recycling slag in large car¬bonated blocks for artificial fish reefs and seaweed cultivation beds. This paper de¬scribes the carbonation reaction, the new process for producing large slag blocks, and the utilization of blocks in past and recent years.

Jan 1, 2004

By S. D. Hudock, C. M. Keran

A review of all upper extremity cumulative trauma disorder (UECTD) injuries was conducted by the U.S. Bureau of Mines for 1985 through 1989. This review was performed by analyzing each injury, as reported by law and maintained on the U.S. Mine Safety and Health Administration's accident data base. This analysis found that incidence rates in mining were lower than in private sector industry, although the number of reported UECTD injuries increased sevenfold and their percentage of all mining injuries increased fivefold from 1985 through 1989. Metal-nonmetal mines accounted for 80 pct of UECTD injuries, while coal mines accounted for 20 pct. Nearly 63 pct of UECTD injuries were accounted for by only four occupations-mechanics, laborers, boney (crusher) operators, and miners not elsewhere classified (NEC)-with an incidence rate well above the private sector industry rate.

Jan 1, 1992

By Staff

The papers contained herein summarize results of various recent Bureau of Mines investigations in the area of mine power distribution systems. They are based on information from Bureau personnel, contractors and grantees, and Mining Enforcement and Safety Administration. Conclusions drawn from a series of parameter measurements on mine power systems, taken over a 3-year span, are presented. Personnel and equipment hazards due to faults on isolated, solidly grounded, and resistance grounded three-phase systems are discussed. Two papers cover dc applications of circuit breakers, including a novel protection scheme for trolley lines. The methods of suppressing induced arcing currents and voltages in a-c machines are evaluated. An evaluation program for ground monitors is described. Acceptance test procedures and the importance of various paparameters for trailing cable splice are covered. A number of techniques for locating faults in trailing cables are described.

Jan 1, 1975

Ravensthorpe Nickel Operation (RNO) is a major new mine and processing plant currently being constructed by BHP Billiton in a ?green field? site near the small town of Ravensthorpe, about 150 km west of Esperance and six hours drive from Perth in Western Australia. Ensuring that the project has a positive overall impact on the surrounding region and that this extends well beyond the life of the operation will be a major challenge for RNO, state and local government, and the local community. For the last two years, the Centre for Social Responsibility in Mining (CSRM) has been assisting RNO management and the RNO Community Liaison Committee to develop a community sustainability monitoring framework for the project. This paper reports on the process that was used to develop the framework, describes the main elements and briefly discusses key learnings from the exercise.

Jan 1, 2007

By D. S. Kostick

Soda ash production in the United States during 1994 increased 4%, reaching 9.3 Mt (10.2 million st). That was the second highest production year. Domestic nameplate soda ash capacity is about 11 Mt (12 million st). Overall, the industry operated at about 85% of capacity. Some companies produced at 100% of capacity while others produced at below their design ratings. Although domestic soda ash consumption was slow during the first half of the year, third- and fourth-quarter sales increased, especially in the flat¬glass and fiberglass sectors. These two sectors increased because of greater demand for glass products in the automotive and construction industries. Soda ash sold for pulp caustic soda increased during 1994. This was due to higher prices for and reduced availability of electrolytic caustic soda. It is often preferred for pulp digestion because of its stronger alkalinity.

Jan 1, 1995

By Gerson de Araújo Filho

This paper shows the use of tires as fuel to be employed into blast furnaces. The tires can substitute coal or even charcoal in the blast furnaces tuyeres. The injection into tuyeres, besides the contribution for energy generation, can also produce gas for iron oxide reduction. The tires, as powder to be injected into blast furnaces, contributes for an environmental use of this waste, which helps to obtain a high value product as well. So, the advantage of using such material is that it is waste and has lower cost for preparation. The obtained results showed that the tires have good combustibility. This one was obtained in a model that simulates the same conditions occurring in the blast furnaces tuyeres; these used raw materiais include tires and mixtures of tires with coal or even with charcoal.

Jan 1, 2006

Accountability for profit realized or lost, and responsibility for continued safe operation are the main impetus behind operator training. Efficiency in operation enables production at lower unit costs. An inefficient operation eats profitability of the operation, creating short term losses, and also affecting longer term viability particularly when commodity prices fluctuate and competition erodes market share. Safe operation and efficient operation are ultimately conjoined entities which may not be able to be sustained without dual effort. Training is a very valuable tool to engage operations in adopting more efficient and safe practices. Training requires time, facilities and trainers. One novel way of minimizing both the trainers and the facilities is through the use of Computer Based systems. Included amongst this are Computer based equipment simulators, following an identical philosophy as flight simulators used for pilot orientation and training for different aircraft types.

Feb 1, 2008

By Richard J. Mainiero, Michael S. Wieland, Harry C. Verakis

The Bureau of Mines, U.S. Department of the Interior, has been conducting research on delay blasting in underground coal mines in support of the efforts of Mine Safety and Health Administration (MSHA), U.S. Department of Labor, to revise coal mine blasting regulations. Part of the research centered on developing an understanding of the factors that lead to misfires of permissible explosives. Research was conducted to determine whether frequency of misfires was related to borehole spacing. For a wide variety of permissible explosives, misfires were observed for about 50 X of the holes at 45-cm (18-in) spacing. Misfires were also observed for 60-cm (24-in) spacing, but the frequency of misfires was much lower than observed for the 45-cm (18-in) spacing. The Bureau has recommended that hole spacings of less than 60 cm (24 in) be prohibited.

Jan 1, 1986

By Dhanvin B. Mehta

Pile testing is generally understood as static load test. It is our common experience that for high capacity, large diameter bored piles, static testing is expensive and time consuming. It is practically impossible to test large number of piles by traditional testing methods. The escalating cost in carrying out a static load test, as well as incomplete information derived therefrom compelled researchers in United States to look for an alternative method of testing for both bored and driven piles. The original research work was carried out at Case Western Reserve University in early 70's, under the funding of Federal Highway Administration as well as several State Depts. of transportation in United States. The outcome of the research was the development of a state of art field computer for capacity determination, based onOne Dimensional Wave Mechanics.

Jan 1, 1996

(Under this heading will be published notes sent to the Secretary of the Institute by members or other persons. ) Position in sales department is open for a mining engineer with experience in mine ventilation and possessing some knowledge of fan design; one competent to lay out ventilating systems to meet various conditions. No. 2. A large company manufacturing mining machinery has an opening in one of its Western agencies for a young mechanical engineer who has had some experience in designing along general machine shop lines, and who is familiar with cost systems. No. 3. A large university desires to secure a prominent metallurgist for a vacant professorship in metallurgy. No. 4. Opening at a mine in New Jersey for a technical graduate to begin work as chairman on the surveying squad. Salary $50 per month to start. No. 5.

Jan 11, 1913

By Harry Verakis, Thomas Lobb

This paper is a summary and an update of the underground mine blasting accident investigations and studies previously conducted by the Mine Safety and Health Administration (MSHA) and the former US. Bureau of Mines. Blasting accidents are usually a small percentage of the total number of mining accidents. However, blasting accidents continue to occur and the severity of these accidents is disproportionately high with respect to other types of mining accidents. In 2000, about 5.7 billion pounds of explosives were produced in the USA. The mining industry consumed the greatest portion of explosives manufactured for blasting with about 67 percent used for coal mining. Metal and nonmetal mining operations account for about 23 percent of the use of explosives. The use of permissible explosives in underground coal mines continues to decline (3,373,069 pounds for 2000).

Jan 1, 2002

THREE regional meetings are planned for this summer and fall following the spring meeting held under the auspices of the Iron and Steel Committee and the Ohio Section at Cleveland in April and in lieu of a general fall meeting of the Institute. Plans for all of them are maturing rapidly. Excellent programs and. interesting visits to points of local tech¬nical interest are already assured. THE SALT LAKE CITY MEETING This meeting will be under the auspices of the Milling Committee and the Utah Section. It will be one of the features of the joint convention held the week of August 22 to 26 with the Western Division of the American Mining Congress. The Congress will be responsible for the general arrangements and for the program on the first day. The following general committees have been appointed:

Jan 7, 1927

By Paul Worsey, Gerald Rupert, Mark Kirkbride

The realignment of Highway H in the proximity of Crystal Cave (Springfield MO.) required the development of a blasting program that was both economical and efficient for construction, yet ecologically safe for the cave. Three component seismographs were strategically placed underground near prominent and sensitive cave features and the vibration levels from the construction blasting continuously monitored. Peak particle velocity (PPV) values were found to obey the square root scaling law and a peak particle velocity value of 0.3 in/sec was chosen as the safe maximum limit. This value proved adequate in preserving the integrity of the cave and its features. Scaled distances for the maximum and lower values enabled blasting personnel to select explosive charge weights per delay for given distance to the cave. Delays were determined from the dominant frequencies recorded underground.

Jan 1, 1997

By J. L. Rodda

A large amount of time has been devoted to the microscopical study of the copper-zinc alloys, emphasis naturally being placed upon the commercially important alloys of the system. Suitable methods are available for microscopically recognizing the two phases richest in copper, Per cent,by weight FIG. 1.-COPPER-ZINC EQUILIBRIUM DIAGRAM. (Frond National Metals Handbook, 1933.) but none appear to have been developed for the positive identification of the other phases. This is, however, accomplished, for the phases normally encountered, by an electrolytic method described in the following pages. Five phases of the copper-zinc diagram (Fig. 1) are considered for the purpose of this paper: the solid solution of zinc in copper, alpha (a); the intermediate phases, beta (ß), gamma (y), and epsilon (e); and the solid solution of copper in zinc, eta (n). Beta prime is not considered a separate

Jan 1, 1936