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By William W. Adams

A larger measure of safety attended the operation of the stone quarries and related plants in the United States during the calendar year 1935 than in any other year for which annual records are available for the industry. The accident rate, covering fatalities and nonfatal injuries that disabled an employee beyond the remainder of the day on which the accident occurred, was 38.19 per million man-hours of work performed. The nearest approach to this favorable record was in 1932 when the rate was 38.48. The rate for 1934 was 41.82; hence the record for 1935 was 9 percent better than that for 1934. Reports from operating companies showed that 51 men were killed by accidents in 1935 and 4,152 men were injured. (See table 37.) The industry employed 73,005 men and performed 110,033,341 man-hours of labor, an average of 1,507 hours of work per man. Measured in man-days, the total volume of labor was 14,623,303, or an average of 200 days of 7.52 hours per day for each man employed. These figures are not strictly comparable with similar figures for the preceding year, as the, coverage of the industry was more complete for 1935 than for 1934 because special facilities were available to the Bureau of Mines for conducting the 1935 canvass that were not available for the 1934 canvass. Reports covering identical plants that were active both in 1934 and 1935 indicate a reduction of about 7 percent in the number of men employed in 1935. This fact suggests that the apparent increase in the number of workers in 1935 is attributable chiefly, if not entirely, to the more complete coverage of operating plants in 1935. The plants from which this inference is drawn employed 21,799 men in 1934 compared with 20,248 in 1935.

Jan 1, 1937

By H. B. Hill

The Salt Flat field, formerly called the Toe -Bruner field, is located northeast of the town of Luling in Caldwell County, Tex. This field, which is a fault structure, approximately parallels and is about 5 miles east of the Old Luling field. The proved area is approximately 1,280 acres, on which 332 producing wells (September, 1930) have been drilled. The majority of the wells are producing from the Edwards limestone at an average total depth of 2,700 feet. A few wells are producing from the Austin chalk or from other formations above the Edwards limestone. The Wilcox formation is exposed, and the fault trace in places is scarcely evident. The strike of the structure is approximately 111. 20 to 45° E. The displacement of the fault is probably 200 to 500 feet. The discovery well was completed in the Austin chalk by the Lutex Oil Co. during April, 1928. In October, 1928, the Sun Oil Co. completed the discovery well in the Edwards pay. This well was an important discovery, as it indicated the potential oil possibilities of the Edwards limestone in echelon fault structures. The discovery led to the development of the third fault field in the Edwards limestone and opened up a large area for future prospecting. The total oil production for the Salt Flat field to and including September, 1930, was 19,833,215 barrels. The most reliable figures available of water production were compiled for a number of leases and wells in the south half of the field. These data show that the water percentage for the average well in this part of the field increased steadily from 30 per cent for January, 1929, to 81 per cent for December, 1929. The estimated daily water production of the entire field for December, 1929, was about 82,000 barrels as compared with a daily oil production of 29,725 barrels; or approximately 2.7 barrels of water were produced with each barrel of oil 14 months after the discovery well was completed in the Edwards pay. Estimates of water production in the (Old) Luling field, which is near the Salt Flat field, place the daily water production at about 150,000 barrels (July, 1929) as compared with a daily oil production of 11,000 barrels. These figures indicate that in the Luling field approximately 14 barrels of water must be lifted for each barrel of oil produced. The Luling field was discovered in August, 1922, and a peak annual production of 10,210,000 barrels was reached during 1924. The production during 1928 was 5,057,000 barrels of oil from an average of 567 producing wells for the year. Although water appeared early in the life of the Luling field, the oil production has been well sustained. Another feature of outstanding interest is the comparatively few producing wells that have been abandoned on account of water during the soven years of operation of this field. Comparison of data between the Luling and Salt Flat fields is of importance because of the nearness of the two fields. The Luling field is a narrow strip or "shoestring" approximately 8 miles long, with a maximum width of 3,400 feet. Production is obtained in the Edwards limestone at an average depth of 2,200 feet on the upthrow side of a fault. Similar conditions of accumulation are found in the Salt Flat field at greater depth to Salt Flat field as outlined (April, 1930) is about 7 miles long? with a maximum width of 2,000 feet. At the time the field work was begun (July, 1929) in the Salt Flat field, drilling operations had been almost completed in the south half of the field, while the north half was still under development. Cross sections and a structure contour map interpret the subsurface conditions in the south half of the field, where the water conditions first became serious.

Jan 1, 1931

By Robert S. Schechter

A minitest of the new potassium chloride-potassium carbonate two-stage in-situ uranium leach process has been carried out at the Intercontinental Energy Corporation (IEC) Zamzow project site in South Texas. Substantial quantities of high concentration uranium were produced indicating the viability of the leach solution. The test results yield information regarding the reservoir dispersivity, the average cation-exchange capacity of the formation, and the distribution coefficients describing cation-exchange reactions. The test also indicates permeability anisotropy and the existence of disturbed flow fields.

Jan 1, 1985

By J. E. Hipp

Three electrostatic field sensing proximity warning devices were tested using full-scale cranes and power line systems, a scaled model facility, environmental testing facilities, and theoretical/numerical analysis. The design objective of each device is to assist in safe crane operation near overhead power lines. Several design deficiencies (varying from device to device) were observed, including inadequate overlap in sensitivity ranges, utilization of vacuum tubes and electro-mechanical parts, temperature sensitivity and inaudible alarms. In addition, the testing showed major device limitations including sensitivity to boom orientations and length, polarization dependent responses, and unreliable operation in the presence of multiple power line circuits. The multiple power line circuit problem is intrinsic to electrostatic sensing devices. The remaining deficiencies and limitations are correctable within a state-of-the-art design. This investigation is not intended to evaluate the safety aspects or policy of utilizing proximity warning devices. Rather, the purpose is to determine the performance characteristics of such devices in relation to the criteria specified in proposed MSHA regulation 77.805-4 (i. e., the devices must alarm at a distance of 10 feet from the power line).

Jan 1, 1980

By Jeffrey A. Shibe

A prototype Fire Safety Evaluation System has been developed and is ready to be evaluated by a Peer Consulting Panel and for performing field tests. The system can be used to determine combinations of widely accepted fire safety equipment and under-ground coal mine features that provide a level of safety equivalent to those required by the Code of Federal Regulations-Title 30 for underground coal mines. In this evaluation, equivalent safety performance is gauged in terms of overall level of safety provided rather than by a component by component comparison.

Jan 1, 1987

By W. A. SLOAN, G. L. Oldright, J. D. Sullivan, E. K. PRYOR, A. F. HALLET, R. S. Dean, S. L. BROWN, F. S. Wartman, A. J. Thompson

Lack of sufficient publication funds has resulted in the accumulation of considerable unpublished experimental work on copper metallurgy by the Bureau staff . The present report gives extended abstracts of this work , as well as a discussion of the best direction for future efforts . The experimental work reported in this series of papers was done in cooperation with the University of Arizona , Tucson , Ariz . The investigations covered in the third , fifth , and seventh papers were done under the direction of G. L. Oldright and the remainder under the direction of V. H. Gottschalk .

May 1, 1934

By D François-Bongarçon

After a review of the progresses made on the liberation factor theory since its inception by Gy (1982), a new and surprising result of great practical importance is presented: the liberation factor. First introduced simply as a number between 0 and 1, then shown to be the ratio of two variances, is now shown to be well approximated by the proportion of liberated mineral.CITATION:François-Bongarçon, D, 2017. Evolution of the concept of the liberation factor and a surprising new result, in Proceedings Eighth World Conference on Sampling and Blending , pp 307–310 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

By René Winand

Due to chemical and electrochemical behavior of the most common additives in copper electrorefining i.e. gelatine, thiourea and chloride ions, it is essential to simulate as far as possible true industrial practice while performing laboratory experiments. The three additives must be studied simultaneously, and added continuously to the electrorefining cell. Ratio electrolyte volume to cathode area; ratio bleed flow to cathode area; hydrodynamic conditions; residence time of electrolyte in the cell; current density; electrolyte and soluble anode must be as near as possible to industrial ones. Experiments performed in the author's laboratory show that under these conditions, reproducible results can be obtained at normal industrial current density and at high current density as well. Problems are however still encountered when developing a sensor for additives monitoring, due to electrolyte redox potential and to substrate influenced thin layer deposition.

Jan 1, 1995

By S Carr-Cornish, K Moffat

Social licence to operate is developed and kept through managing both operational impacts and the relationship between local community and company. However, CSIRO research has demonstrated that in determining how accepting community members are of a mining operation, relational factors, such as procedural fairness and trust, are much more important than operational impacts, such as impacts on employment and the environment (Moffat and Zhang, 2015). Companies seek to develop relational factors through their engagement with local community; such engagement has many aspects, including, initially identifying stakeholders and positioning the company as part of the local community (Lacey et al, in prep; Thomson and Boutlier, 2011). These relational factors involve the social identities of people living in the community. Social identities are a part of people that shape their beliefs, based on their connections with various groups in their lives (Hogg et al, 2004).An engagement process, intentionally or not, inevitably interacts with the social identities of stakeholders (Crane and Ruebottom, 2011). For example, traditionally, at the very beginning of engagement processes, community members are assigned to categories using conventional stakeholder mapping and categorisation methods, often based on assumptions about stakeholders’ interests, which equates to assumptions about stakeholders’ social identities (Colvin, Witt and Lacey, 2016; International Council on Mining and Metals, 2012). Yet, there has been limited empirical inquiry into whether such categories reflect the social identities of stakeholders and if there is a bearing on relational factors, including, the perceived fairness of consultations and trust in mining companies (Crane and Ruebottom, 2011). Also at this time, companies commonly seek to create a presence in communities, for example, joining Chambers of Commerce and participating alongside community members. Again, there has been limited empirical inquiry into whether community members and companies identifying with the same overarching group and thus sharing aspects of social identity, influences relational factors (Crane and Ruebottom, 2011). In this study, we examined the effects of changing aspects of social identity by changing how stakeholders were identified and companies were positioned, on how stakeholders’ perceived a new mining operation, specifically how they perceived the procedural fairness of the proposed consultation process and trusted the company, two factors that underlie a company’s social licence to operate.CITATION:Carr-Cornish, S and Moffat, K, 2016. Out of the box – the power of social identities in engagement processes, in Proceedings Life-of-Mine 2016 Conference, pp 180–182 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By D. Seneviratne

Iron transfer from the pregnant leach solution (PLS) to the electrolyte can have a major economic impact on solvent extraction (SX) operations. High iron transfer will lead to greater operational costs, due to increased reagent consumption through electrolyte bleed and make up, or increased power costs due to decreased electrowinning current efficiency. Bioleaching of low-grade copper sulfide ore from the Kennecott Utah Copper Mine was investigated in a large scale piloting program including SX and electrowinning. Plant data and lab test work conducted throughout the course of operation, show that the unique containing PLS high ferric iron with high pH can lead to lower Cu: Fe selectivity than is typically seen in traditional copper SX operations. The impact of high ferric iron on the plant operation, and methods to reduce iron transfer will be discussed. Special considerations need to be taken for plant operating conditions and selection of SX reagents (including both extractant and aromatic content of diluent) based on the feed PLS characteristics.

Feb 23, 2014

By C. M. Jones

The training program developed at Sierrita over the last twelve months has led to several significant improvements in both safety performance and productivity. Our most easily quantified results have been in truck productivity, where we have also experienced a 6% decrease in truck cycle times. We feel this is due to increased skill levels and awareness on the part of our operators due to our new training effort. The cycle time improvement has resulted in an increase in Truck productivity of 6%. Costs associated with productivity training have been $160,300. This includes program development and execution costs, as well as lost productivity during the training itself. These costs are offset by $1,400,000 in savings directly attributable to the increased skill levels of our technicians due to our training effort. As such, this represents a solid, high return investment at Sierrita.

Jan 1, 1998

By P. E. Auger, J. E. Gill

"The zinc deposits to be described are in Lemieux township a few miles south of the Tabletop mountains, in the central part of Gaspe peninsula, Quebec. Although they have not been worked, they constitute a potential source of zinc and lead and structurally are of considerable interest.GENERAL CHARACTER OF THE OCCURRENCEThe deposits are in sharp-walled quartz-carbonate veins and breccia zones carrying locally, and in varying amounts, sphalerite, galena, pyrite, marcasite, chalcopyrite, and specularite. Those so far investigated strike generally north-south, have steep dips, and cut through sediments of Lower Devonian age, mostly calcareous argillites or siltstones. Wall-rock alteration is negligible.BROADER STRUCTURAL FEATURESThe principal known occurrences are in the south-central part of a dome structure measuring 6 by 5 miles. The argillaceous sediments are overlain, on the flanks of the dome, by sandstones and lavas. These have been stripped from the central part of the dome, revealing the veins in the argillites beneath. The veins formed after the volcanics, but the fractures and breccia zones in which the deposits formed are confined mainly to the argillite series, presumably because of the greater strength of the lavas.The argillite series is cut by dykes, sills, and small stocks of diorite and acidic 'porphyries' that are older than the veins.THE FEDERAL HILL AREAThe distribution of known veins is shown in Fig. 1. The characteristic features of the veins are well illustrated by the Federal Hill area shown in Figs. 2, 3, and 4, and described below."

Jan 1, 1954

In its largest product launch in company history, Cummins Engines welcomed more than 200 customers, vendors and media to witness the unveiling of its new QSK95 engine at its Seymour Engine Plant in Seymour, IN on Nov. 1. It took the efforts of 150 engineers to design the QSK95 and more than $100 million in investments to establish a new production line and test facility at Cummins? Seymour Engine plant. The result of these efforts is a new platform of engines that Cummins says will provide as much as 2,983 kW (4,000 hp) and will be the most powerful, high-speed diesel engine ever built.

Jan 1, 2012

By J. G. Groppo

Laboratory settling and filtration testing was conducted on wet processed fly ash in order to determine the applicability of conventional dewatering techniques to reduce the moisture content prior to drying. Settling tests showed that acceptable clarity (<1.5 g/l suspended solids) could be achieved after as little as 6 minutes of settling. After settling to a consistency of 40 weight % solids, continuous laboratory vacuum filtration testing produced a cake containing below 20% moisture with throughput exceeding 150 lb/ft2/hr.

Jan 1, 1997

By L. Hales

Neural networks are a generalized, multivariable non-linear modeling technique that can be used to model mineral processing operations. Neural networks will be described as will their use in modeling column flotation. Optimization of column flotation will be explored and discussed by using the neural network column models.

Jan 1, 1996

By F Shi, G Ballantyne, K Runge

There has been minimal innovation in the methods used to process an ore over the last 50 years. Productivity increases have largely resulted in increased equipment size without implementation of parallel improvements in technology. Complex orebodies of the future will need mining operations to adopt new technologies and techniques to make future ore treatment economically viable. Three emerging technologies, namely high voltage pulse (HVP) pretreatment, fine screening and the HydroFloat&lt;sub&gt;TM&lt;/sub&gt; coarse particle flotation cell will be presented in this paper and the potential benefits that may result if they are adopted in mineral processing circuits will be outlined. The barriers that must be overcome before they can be adopted by industry with confidence will also be discussed. CITATION: Runge, K, Shi, F and Ballantyne, G, 2018. New technologies that will potentially enable processing of complex orebodies, in Proceedings Complex Orebodies Conference 2018, pp 126–129 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

To maintain its brand position in the competitive market of mining equipment, the Volvo Construction Equipment (Volvo CE) engineers were challenged to develop top-performing wheel loaders and articulated haulers even faster than before. To start, this meant reducing prototype test cycles by two-thirds. The final goal? Chopping in half the virtual prototyping time in early design phases. Creating a unified co-simulation solution In this ground-breaking project, the Volvo Construction Equipment design team in Eskilstuna, Sweden, replaced its piecemeal department-by-department process with a single solution based on LMS Imagine.Lab AMESim. With one unified model, they could simulate the behavior of four major vehicle subsystems in wheel loaders and articulated haulers: hydraulics, powertrain, thermal management and the actual driver. Subsystem models exchanged data seamlessly.

Jan 1, 2011

By Thomas Niehoff

"Oxyfuel combustion systems are state of the art for many melting operations. Airfuel systems have been stepwise modified to oxygen enrichment, oxygen lancing and oxyfuel. Every change of the melting process will have consequences with regards to emissions and energy usage. The uniqueness of many operations requires unique skills to resolve potential issues. This paper will give some examples of how airfuel systems can successfully be converted to oxyfuel.IntroductionOxyfuel technology – meaning the combustion of fossil fuels such as natural gas, oil or coal with technical oxygen instead of air for industrial melting or heating processes is widely used in many industries these days. Even though oxygen production, storage and handling has been state of the art for decades other opinions exist. Often oxyfuel is regarded with fear and potential hazards like: “Oxygen makes the process too hot.”, “Oxygen will melt away the refractory.”, Liquid oxygen is dangerous.”, “Oxygen will cause explosions.”, ……etc.Typically a more detailed discussion about a specific industrial process and how oxygen can be applied in a safe and economic way the seeming issues go away."

Jan 1, 2010

By M. Piard

The scarcity of literature referring to mines in the Rockies has compelled the writer to co-ordinate information and advice taken at the very source. Help was gladly given by active inspectors and mine bosses. Although the field is unimportant at the present time, due to its distance from markets for raw coal, it is quite worthy of the attention it is receiving from two continents; for, with the commercial synthesis of liquid fuels, it would become the largest fuel laboratory in the world, provided, of course, that freight cost drops to a low comparative level. As explained below, there are no obstacles to economical and safe operation under anything like the typical outcrop shown in Figure 1. Although coal dust is probably more dangerous in the Rockies than anywhere else, the damp outcrops afford means of control. The abundant gas may be bled to the open air, and the rigid roof will settle gradually under a wide span of opened outcropping. The Panel Retreating Wall The Measures: Coal measures having an attitude similar to that shown in cross-section in Figure x are characteristic of the active coalfield on the Alberta side of the Rockies, and they are also found on large tracts of undeveloped land west of the divide. The small anticlines, not shown in the cross-section, do not affect the progress of a pillar line, provided their crests are connected to the atmosphere by drainage bore-holes.

Jan 1, 1928

By William Gleason

"In 2008, the world quietly hit a milestone that did not receive much fanfare or publicity, but it hit one that marked a turning point in the history of mankind and the way the planet is and will be inhabited in the future. It was in 2008 that, for the first time, more than half of the world’s population, an estimated 3.3 billion people, resided in urban areas. The world’s population had moved from being a majority of agricultural and rural society to an urban society. Andrew Whalley, deputy chairman for Grimshaw Architects, said this change in where and how people live will continue to increase urban populations and, by 2050, it is estimated that more than 6.4 billion people will live in urban areas. To meet these needs, Whalley, speaking during the keynote session of the 2105 Cutting Edge conference in Denver, CO, said future cities will have to be reimagined and redesigned to be more efficient. A large part of that design will be in the infrastructure of those cities.At the Fourth Annual Cutting Edge Conference, Sept. 21-23, much of the discussion was around how the tunneling and underground construction industries improve cities in a number of ways, including societal, environmental and in overall efficiency. There was talk, not just about the improvements that society enjoys at the completion of such projects, but also about the challenges faced by the owner and contractor in the construction of such projects.The conference, titled Urban Tunneling, brought together some of the top minds in the industry to not only discuss the issues faced today, but also those that will shape the industry in the future.For his part, Whalley spoke about a number of projects around the world and how they have impacted society in ways beyond simply providing a better means for transportation of people or water. Notably, he spoke about the Crossrails project in London.London is a city of 8.6 million people and a history that dates back nearly 2,000 years. It is a great example of the challenges the industry faces in bringing modern efficiencies to an established city.Running more than 100 km (62 miles) with more than 42 km (26 miles) of tunnels passing through 40 stations, including 10 new stations, the project is the largest in Europe and will transform the way people move about the city."

Jan 1, 2015