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By Eugene T. Sheridan

This report presents statistical data on individual plants in the fuel- briquet and packaged-fuel industries circularized by the Bureau of Mines, United States Department of the Interior, in its 1957 annual survey. This survey revealed that 17 briquet and 23 packaged-fuel plants were active part or throughout the year. The annual production capacity of the fuel-briquet industry was 3,088,000 net tons, a decrease of 17 percent from 1956. The decline in capacity was caused in part by the permanent retirement of 4 plants and also by the reduction in capacities of 4 other plants. The rate of production of briquet plants also decreased as the industry operated at 35.8 percent of capacity compared with 40.9 percent in 1956. Every operating plant in 1957 had an annual capacity exceeding 25,000 tons.

Jan 1, 1958

By O. L. Culberson, J. J. McKetta

Experimental and smoothed data are presented for the solubility of methane in water for temperatures of 77, 100, 160. 220. 280, and 340°F at prejsures to 10.000 psia. The minimum solubility phenomenon exists within this temperature range to pressures of 10.000 psia. INTRODUCTION The study of hydrocarhon-water systems has been extended to the determination of the solubility of methane in water at pressures to 10.000 psia. The experimental apparatus, and the technique. are the same as that previously reported.' - In the determination of the solubility of methane in water, only two phases were present at temperatures between 100 and 340°F. these being the vapor phase and the water-rich. liquid phase. The determinations involved the agitation of methane and water in an equilibrium cell. withdrawal of a sample from the liquid phase, and the analysis of the sample. The experimental value; determined in this manner are pre9ented in Table I and in Fig. 1. Since experimental and analytical techniques have improved since the initial experiments with this equipment, it was decided to repeat the 77°F isotherm determinations.' Fig. I shows that the individual results for this isotherm are much

Jan 1, 1951

By J. J. McKetta, O. L. Culberson

Experimental and smoothed data are presented for the solubility of methane in water for temperatures of 77, 100, 160. 220. 280, and 340°F at prejsures to 10.000 psia. The minimum solubility phenomenon exists within this temperature range to pressures of 10.000 psia. INTRODUCTION The study of hydrocarhon-water systems has been extended to the determination of the solubility of methane in water at pressures to 10.000 psia. The experimental apparatus, and the technique. are the same as that previously reported.' - In the determination of the solubility of methane in water, only two phases were present at temperatures between 100 and 340°F. these being the vapor phase and the water-rich. liquid phase. The determinations involved the agitation of methane and water in an equilibrium cell. withdrawal of a sample from the liquid phase, and the analysis of the sample. The experimental value; determined in this manner are pre9ented in Table I and in Fig. 1. Since experimental and analytical techniques have improved since the initial experiments with this equipment, it was decided to repeat the 77°F isotherm determinations.' Fig. I shows that the individual results for this isotherm are much

Jan 1, 1951

By W. K. Hartley

INTRODUCTION AND HISTORY The Kimberley Division of De Beers Consolidated Mines Limited includes four underground mines in Kimberley viz. Dutoitspan, Bultfontein, De Beers and Wesselton Mine and two outside mines, viz. Finsch, an opencast operation and Koffie- fontein, an underground operation. Figure 1 is a map of the Kimberley district showing the location of these mines. Finsch is 150km west of Kimberley and Koffiefontein is 80km south of Kimberley. The head office of the De Beers Company is in Kimberley. The diamond sorting and trading companies for diamonds produced in South Africa are also in Kimberley. Diamonds were first discovered in the Kimberley area at Hopetown in 1866 on the banks of the Orange River. This, and later finds, triggered the start of the great "Diamond Rush". In 1870 the Jagersfontein (now closed) and Dutoitspan pipes were discovered, followed by those at Bultfontein, De Beers and Kimberley Mine (now closed) in 1871, Koffiefontein in 1880 and Wesselton in 1891. Finsch Mine was a more recent discovery in 1961. Finsch, due to go underground in 1986, and Koffiefontein, are fully self-contained with their own treatment plants, housing, services etc. The four Kimberley mines deliver ore by conveyor to a central treatment plant and use joint ser- vices. ,+lining is presently carried out mainly by Block Caving which has replaced the earlier Chambering method. De Beers Mine, on a limited scale, and Wesselton Mine have recently started to use Sub-Level Caving, and both Bultfontein and Du- toitspan are scheduled to use the same method at a later date. The combined ore tonnage produced by the Kimberley Mines is 17 400 tons per day, Koffiefontein 12 000 tons per day and Finsch Mine 17 000 tons per day. THE EVOLUTION OF MINING METHODS Initially, the open-cast mining was carried out to as great a depth as safety would permit. In the early stages of open-cast mining, the Kimberlite was removed in horizontal slices from levels 13m to 20m apart. The rock broken in the workings was raised to the surface by means of endless rope haulage inclines. As lower levels were attained these rope haulages were replaced by aerial hoists, inclined shaft haulages or inclined skip-ways. These methods were dependent upon the strength of the unsupported pipe walls, which became increasingly unstable with depth and a system was adopted whereby the ground mined in open excavations was tipped down passes to tunnels connecting with vertical hoisting shafts sunk in the country rock. As work in the open pit became more and more impracticable due to extensive falls of ground, this system was replaced by a combination of open-cast and underground mining, and eventually by wholly underground methods. Chambering With the advent of underground mining, a system known as "Chambering" (or "Inclined Chambering") was evolved. It was essentially a combination of shrinkage stoping and caving, whereby advantage was taken of the high pressure exerted by the loose rock that had accumulated in the open excavations due to the collapse of the pipe walls. This mining method was introduced around 1890 and was successfully employed, with little change, up to the early nineteen seventies. In this system each mine was served by a main hoisting shaft situated about 300m in the country rock. Main haulage cross cuts were driven from the shaft to the pipe at 200m (600ft) vertical intervals. A sub-vertical shaft, situated close to the pipe provided access to the working levels. Chamber levels were established from the sub-vertical shaft at 13m (40ft) intervals. See figure 2. On each of these levels successive 6,8m wide “cuts" were mined out across the pipe, from one rock contact to the other, and extended vertically to the footwall of the level above. Every 6,8m cut was made up of a chamber and a "back-pillart1, each approximately 3,401 wide. The chamber was mined by overhand shrinkage stoping. The levels were carried "en echelon", with each chamber on a level approximately three cuts ahead of the chamber on the level

Jan 1, 1981

By Fernando Velazquez Guzman

Titanium is an alloying element used to refine grain size in steel and improve its physical and mechanical properties. In some stainless steels it is used to increase the resistance to corrosion by the precipitation of titanium carbides or carbonitrides. Its alloying performance is highly variable and depends largely on the stage of the secondary metallurgy process when it is added. Furthermore, the addition method (wire injection or direct addition) has a remarkable influence in secondary refining. This paper describes the tests performed in vacuum degasser (VD), with a highly compacted and encapsulated Ferrotitanium wire (FeTi HC). The yield of titanium in steel increased from 52% to 89%. Moreover, the consumption of the highly compacted Ferrotitanium was optimized.

Oct 30, 2017

By G. Vijaya Kumar, B. Srinivasa Rao, G. V. Krishna Rao

The paper outlines the ventilation practices prevailing in coal mines of Singareni Collieries Company (South India). The high annual average surface temperature and relatively steep geothermic gradient results in virgin strata temperatures in the region of 38- 42°C creating environmental problems in the working places. Expensive methods of air cooling can not be employed as the mines are small, and production and productivity do not justify the costs of artificial cooling of mine air. Controlled recirculation of mine air -- the unconventional technique being tried with success in some coal mines in U.K. has been analysed for improving the environmental conditions. The analysis shows that the method is safe, cost effective and can be applied with very little extra equipment.

Jan 1, 1991

By T. Feroze, B. Genc

"The ventilation of underground coal mines plays an important role in minimizing the risk of methane and coal dust explosions. The ability of ventilation, with the use of line brattices (LBs), to remove methane and coal dust in empty headings is dependent on the amount of air leaving the LB and entering the heading. The quantity of this air depends on the associated system variables, namely heading dimensions, settings of the LB, and velocity of air in the last through road (LTR). However, the exact effect of these system variables on the flow rate at the exit of the LB in an empty heading is not known. The installation of LBs in South African coal mines is generally carried out based on experience. This can result in overor under-ventilation and may increase the cost of providing ventilation or cause accidents, respectively. In this paper, using computational fluid dynamics (CFD), the air flow rate at the exit of the LB in an empty heading was estimated using full-scale three-dimensional models. The CFD model used was validated using experimental results Firstly, the settings of these three system variables were varied, the flow rates at the exit of the LB were measured, and finally the results were used to calculate the effect of each system variable. The outcome is a mathematical formula that can be used to estimate air flow rate at the exit of the LB in empty headings for any practical scenario.This paper will help the coal mining sector in South Africa by providing estimation models based on scientific reasoning for the installation of LBs, and will also serve academia as part of the curriculum towards educating future mining engineers."

Jan 1, 2016

By J. C. Bartlett

The following discussion was suggested by an experiment of Mr. Krom, the Manufacturer of air-jigs, to illustrate the superiority of air over water as a medium of concentration. The paper is written in the interest of no system of concentration, but simply to test the experiment, and, perchance, to add something to the general fund of information on the subject. To speak of testing an experiment by a theoretical discussion, may seem a misuse of terms, but the theories concerning falling bodies and the resistance of fluids are pretty well crystallized into laws, which may properly be used to show where experiments which seem to refute them were improperly performed, and that instead of refuting they only corroborate. It is well known that a sphere of galena & inch in diameter, and a sphere of quartz 1/2 inch in diameter, are equal falling in water ; that is, these two spheres, being placed together in a column of water at rest or in motion, will practically remain together, filling or rising together, or remaining in suspension. Mr. Krom, to show that these

Jan 1, 1879

By M Rauer

With a worldwide growing population the demand for higher living standards, food and the development of new technology is rapidly rising. To allow for a continuous growth, larger quantities of minerals and raw materials are needed at a faster pace. Different methods have been developed to access or tap ore more quickly, such as improved drill and blast operations, mechanical mining methods using equipment such as roadheaders (RH), longwall miners and other technical equipment. Another possibility to access and develop mines faster is the use of a tunnel boring machine (TBM).The historical usage of TBMs is surprisingly long, but the opportunity for technology adoption by the majority of worldwide mining companies remains largely untapped. Dozens of full face TBMs have been used by mines around the world, including two that will begin operation soon in Australia. TBMs have been used to safely and rapidly gain access to the orebody, or to expand access to the orebody to increase output by running a TBM along the edge of the orebody for several kilometres. These machines have also been used for ventilation and for conveyor tunnels for ore removal. They have been used to quickly excavate long and winding declines giving access to an orebody at several levels in a short period of time.Tunnel boring technology can be used for mine declines, mine access tunnels and all sorts of different mine designs and set-ups. TBM technology simply needs to be adapted to the mine conditions and, if manufacturers are involved early on in the planning process for mine development, the operation can be very successful. In some cases, historically typical mine designs may need to be re-thought.One mine, the Stillwater Platinum mine in Nye, Montana, is currently employing its fourth TBM in 25 years. Two were used to create tunnels running alongside the orebody, rapidly expanding access to the orebody in many locations for increased output. Two were used to create parallel access tunnels to a mine expansion at the East Boulder orebody; one tunnel is for conveyor haulage and the other for vehicular access. TBMs have been employed successfully many times to rapidly drive vehicular decline tunnels to multiple mine levels, such as at the San Manuel – Magma Copper mine in the USA. While TBM technology may not seem to be optimal for every mine, these success stories show that the method can provide vast benefits for the right projects.Early use of TBMs in extremely hard rock metal mines, in the 1960s and 1970s, had limited success since performance was low. However there have been great improvements made over the years in the strength of rock which can be excavated by TBMs with high performance. Other important improvements involve the provision of a safe work environment, safely and rapidly supporting the rock and predicting geology ahead of the TBM.This paper will briefly note the more than 20 TBM mining projects and highlight some notable successes. It will then go on to give a status report on the two active TBM mining projects in Australia and the difference between a TBM operation versus other excavation methods such as drill and blast (D&B) or RH excavation.CITATION:Rauer, M, 2014. Tunnel boring machines in mines – a?brief review of past use with a status report on use today in Australia, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 663–670 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By Guoxiang Chi

The Cornwallis Fold Belt in the Canadian Arctic Archipelago contains numerous Mississippi Valley-type (MVT) Zn- Pb occurrences and the world-class Polaris deposit. The occurrences are mainly hosted by the dolostone in the Thumb Mountain Formation which spreads over 25000 km2. Success in exploration requires further understanding of the genesis of these occurrences and an assessment of their parentage with the giant Polaris deposit. Syn-sulfide dolomites in regional occurrences share C-O-Sr isotopic characteristics similar with Polaris dolomites, indicating warm basinal brines enriched in 87Sr. The dolomites and sphalerites contain fluid inclusions with ice-melting temperature between ?45° and ?25°C, which is significantly lower than for most MVT districts in the world (?30° and ?10°C). These characteristics indicate that all the Cornwallis occurrences were produced by fluids of the same sources and/or aquifers. The deposit size was largely controlled by the rate and duration of the metal-carrying fluid flow, and by the availability of reduced sulfur at the site of mineralization.

May 1, 2001

By R. H. Smith, A. C. Polk

The physical properties of the materials are listed, together with a short explanation of how this material binds the sand grains together without materially reducing the effective permeability of the sand. The chemical can be used in wells with bottom-hole temperatures ranging from 105°F to more than 350°F A description of the equipment required and the techniques used for applying these plastics to the wells is included. Introduction Recovering oil and gas from unconsoli-dated sand formations offers one of the most troublesome of all production problems. These sands generally present no particular trouble while drilling is in progress, but after the well has been completed and a pressure differential has been established across the face of the producing zone, the formation begins to L'slough," resulting in "sanding up" of the well. The term "sanding up" means that sufficient volumes of sand have moved into the well bore or casing to cause a serious reduction or complete halt of all flow of oil, water or gas. In rare cases a well may produce only a small amount of sand and still continue to flow or pump, the sand being carried to the surface in the fluid stream. However, in such instances, the result may be a costly repair bill due to the effect of the sand on surface and pumping equipment. The difficulty of producing petroleum from sands that are loosely cemented has long been recognized by petroleum engineers but only within the last few years has any new approach to the problem been undertaken. This involves the use of plastics that are capable of bonding the individual sand grains in place without materially reducing the effective permeability of a formation. The successful application of plastics for the consolidation of poorly cemented sands is relatively recent but now it is widely used in many of the more difficult areas on the Gulf Coast of Texas and Louisiana. This relatively new use of plastics1 in the oil fields has been preceded by much laboratory and field research on the use of various chemicals2,3 for solving numerous well-completion and work-over problems. Plastics now are being used successfully to control gas-oil and water-oil ratios,4'6 in zone isolation, the repair of casing leaks, the elimination of caving in cable-tool drilling wells6'7 and in the setting of linerss and casing.9 Sand-consolidating plastics, however, are basically different from all others in that they must not form an impervious seal. Field Practices The approach to the sanding-up problem usually has been the mechanical obstruction of the movement of the sand grains.

Jan 1, 1947

By A. C. Polk, R. H. Smith

The physical properties of the materials are listed, together with a short explanation of how this material binds the sand grains together without materially reducing the effective permeability of the sand. The chemical can be used in wells with bottom-hole temperatures ranging from 105°F to more than 350°F A description of the equipment required and the techniques used for applying these plastics to the wells is included. Introduction Recovering oil and gas from unconsoli-dated sand formations offers one of the most troublesome of all production problems. These sands generally present no particular trouble while drilling is in progress, but after the well has been completed and a pressure differential has been established across the face of the producing zone, the formation begins to L'slough," resulting in "sanding up" of the well. The term "sanding up" means that sufficient volumes of sand have moved into the well bore or casing to cause a serious reduction or complete halt of all flow of oil, water or gas. In rare cases a well may produce only a small amount of sand and still continue to flow or pump, the sand being carried to the surface in the fluid stream. However, in such instances, the result may be a costly repair bill due to the effect of the sand on surface and pumping equipment. The difficulty of producing petroleum from sands that are loosely cemented has long been recognized by petroleum engineers but only within the last few years has any new approach to the problem been undertaken. This involves the use of plastics that are capable of bonding the individual sand grains in place without materially reducing the effective permeability of a formation. The successful application of plastics for the consolidation of poorly cemented sands is relatively recent but now it is widely used in many of the more difficult areas on the Gulf Coast of Texas and Louisiana. This relatively new use of plastics1 in the oil fields has been preceded by much laboratory and field research on the use of various chemicals2,3 for solving numerous well-completion and work-over problems. Plastics now are being used successfully to control gas-oil and water-oil ratios,4'6 in zone isolation, the repair of casing leaks, the elimination of caving in cable-tool drilling wells6'7 and in the setting of linerss and casing.9 Sand-consolidating plastics, however, are basically different from all others in that they must not form an impervious seal. Field Practices The approach to the sanding-up problem usually has been the mechanical obstruction of the movement of the sand grains.

Jan 1, 1947

By L. Scott, M. A. Goncalves

Effective communication is a sought-after non-technical skill in the health, safety, and environmental (HSE) function and is fundamental in achieving an organization’s safety objectives. While different channels are used to communicate HSE matters, many organizations employ posters, videos, and/ or signs containing images to convey information. Communication through signage and graphical hazard symbols has been regulated in standards, but vast sections of HSE communication are bespoke communications and exist outside the sphere of standards. Effective HSE communication through images requires an understanding of the organizational culture in which the images will be used, as well as an understanding of the semiotics of the images themselves. Creative interpretation within HSE communication can create situations where the message that was received is not the message that was intended, leading to confusion and misinterpretation. This paper is aimed at elucidating the semiotics of South African HSE visual content. It was found that the indexical mode of images was most preferred in visual communication, and text-only designs the least preferred. Senders and receivers of messages differ in their opinions on the complexity of HSE communication.

Feb 2, 2021

The New Zealand experience has shown that the trend in technologi- cal change in gold extraction can be characterised by a systems approach which grows progressively broader with advances in understanding and allowing for an increasing number of factors. The Australian experience has demonstrated that the elements of developing an exportable process include allowing projects to prolifer- ate where substantial entrepreneural involvement is likely to occur. In both countries useful technological breakthroughs were invariably discarded when first tried at operations not well established and under great pressure of achieving and maintaining production. It required the efforts of persistent individuals at operations which had become bedded in and profitable, to follow the initial work up and commercialise it.

Jan 1, 1988

By S. W. Nicholson, L. G. Woodruff, K. J. Schulz, W. E. Cannon

The 1.1 Ga Midcontinent rift of North America has many similarities to the geology of the Voisey's Bay region in Labrador and the geology of the Noril'sk region in Siberia. These similarities include the hosting of large volumes of sulfur- undersaturated and trace-element-enriched basalt, having igneous centers characterized by crustal contamination, being characterized by metal depletions in some mafic units (an indication of prior sulfide segregation) and having known occurrences of Ni-Cu sulfide mineralization. These similarities along with new geophysical data and refined models for Ni-Cu sulfide deposits suggest that the Midcontinent rift probably contains undiscovered Cu-Ni [±] PGE sulfide deposits, some of which could be the size and grade of a Voisey's Bay or Noril'sk deposit. In particular, intrusions and related feeder systems that occur in northern Michigan and Wisconsin, as well as to the southwest along the rift margin, deserve serious examination.

Jan 1, 1999

By Gustavo Huerta Valer, Jorge Cárdenas Miranda, Johan Salas Flores

One of the challenges of mining is the optimization of the blasting process, which has an important impact downstream in the processing of crushed ore in the plant, that is why mining companies ensure the results of granulometry obtained from the blasting process through a joint work with companies specialized in the process of loading with explosives.

Feb 6, 2023

By Smith F. A, Both R. A

The application of biogeochemical methods in mineral exploration in the semi-arid to and environment of Western Australia was investiga- ted in an area near Norseman. The reliability of these methods was evaluated by comparing trace element characteristics of rock, soil and plants in the vicinity of the Pioneer BB pros- pect. The prospect is located in the south- western part of the Pioneer Dome, where granite gneiss core is surrounded by a 'greenstone' sequence of ultrabasic, basic and sedimentary rocks. Nickel-iron sulphide mineralization occurs discontinuously along one of the basic- ultrabasic contacts. Analyses of unweathered and partly weath- ered rock from diamond drill cores show the ultrabasic rock to be highly variable with re- spect to nickel, copper, cobalt, zinc and manga- nese. Samples of weathered bedrock and over- lying soil were analysed both for total trace element contents and for the trace elements associated with secondary iron and manganese oxides. Approximately 30 per cent of the total nickel content of the weathered basic rock is associated with secondary iron and manganese oxides, compared to approximately 15 per cent in the weathered ultrabasic rock. The soil is partly transported but has a residual component sufficient to provide a reli- able indication of the underlying rock chemistry, although the trace element content of the soil is less variable than that of the rock. Total

Jan 1, 1973

By Jean Balech

This paper presents some results of dynamic loading tests performed on concrete piles driven in soft clay formation. The load transfer mechanism, measured in the dynamic increasing energy test (DIET), under blows of growing energy, is described in terms of mobilized normal forces diagrams and unitary local friction and displacements. It was observed that the lateral skin friction grows up to a maximum, in the soft clay layer and, gradually diminishes to a residual value when the system presents the maximum mobilized resistance. It may be concluded that the rupture load is not equal to the maximum mobilized point resistance plus the maximum mobilized local friction as suggested by most of static bearing capacity formulae.

Jan 1, 2002

By L Xiong, W J Shi, J H. Wei

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Baizhangzi gold deposit is located in the northern North China Craton. The structural and lithological controls on the location and geometry of orebodies were studied through geologic survey, ore spatial configuration analysis and structural analysis. The orebodies of the deposit comprise auriferous quartz-sulfide veins and disseminated gold-bearing sulfides. The auriferous quartz-sulfide veins are dominantly hosted by the NNE- (and NE- and NW-) trending faults, which are subsidiary structures of the regional NNE-trending F2 fault. The subsidiary NNE-trending faults, having sinistral reverse kinematics, are associated with the sinistral reverse kinematics event of the F2 fault, which happened under a regional S–N-oriented compression stress field. The subsidiary NE- and NW-trending faults appear to be compressive and extensional respectively. These NE- (and NW-) trending faults are restricted to the granite intrusion and are associated with a sinistral strike-slip event of the F2 fault, which reactivated under a NW–SE-oriented compression stress field. It makes significant influence on geological evolution and distribution of different ore types that the strike of the F2 fault presents significant transition from NNE- to NE-trending in vertical. The ore-bearing disseminated host rocks, with widespread silicification and pyritisation, distribute in the lower inner contact zone of the granite intrusion, especially in the lower wavelike boundary of granite intrusion.CITATION:Xiong, L, Wei, J H and Shi, W J, 2015. Structural and lithological controls on the location of orebodies in the Baizhangzi lode gold deposit in western Liaoning Province, China, in Proceedings PACRIM 2015 Congress, pp 193–200 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By H P. Rossmanith

This contribution addresses the advanced blasting technology which is based on wave propagation theory and fracture mechanics. The new concept of sonicity and the principle of maximizing sonicity in blasting as well as the energy or work of a blast operation will be introduced. It is shown that - in contrast to common belief – it is not the velocity of detonation which controls the blast but the relationship between velocity of detonation and the wave speeds, in other words, the Mach numbers of the blast operation. Based on numerous practical blasts in Germany, the authors show that, when using wave dynamic concepts, there is a linear relationship between peak particle velocity and the work of a blast operation and this linear relationship is controlled by the sonicity of the blast. Extensions to layered and faulted rock masses are presented. It will become clear that a second change of paradigm is enforced, the first one being the implementation of short time delaying. Again, the acquisition of knowledge in wave progation theory and fracture mechanics becomes mandatory in advanced blasting technology, where the art of blasting is now fully transformed into a science of blasting with little room for methods of trial and error.

Jan 1, 2010