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By Jr. Oitto

A polyester-type resin and deformed-steel reinforcing bars (rebars) were used in to strengthen and to stabilize bolted, fractured wall rock along pas 1:'y. in a western gold mine. Reinforcing bars were placed in boreholes drilled into fractured rock and then were surrounded by resin pumped under pressure into the holes and intersecting fractures until the wall rock was thoroughly impregnated. Pumping and injection equipment and infusion procedures are described. Visual examinations for movement in bonded and adjacent unbonded rock were made for 3 years. Fractured walls containing resin-rebar installations were strengthened. The results suggest that resin-rebar support can be used advantageously and economically in repairing fractured or broken rock when compared with rock bolting or timbering.

Jan 1, 1965

By Sebastião Ribeiro, Leonardo Carneiro Sardinha, Alline Sardinha Cordeiro Morais, Carlos Maurício Fontes Vieira, Sergio Neves Monteiro

The glass tube of spent fluorescent lamps is contaminated with mercury, which might be a serious hazard in the case of conventional recycling by melting with other glasses. A possible solution could be its incorporation into a clay body to fabricate common fired ceramics such as bricks and tiles. The objective of this work is to characterize a type of fluorescent lamp glass waste to be incorporated into a clayey ceramic. The characterization was performed in terms of wettability tests to evaluate the interaction between the surface of the clayey ceramic and glass waste as a function of the firing temperature. The results showed that the contact angle decreased with increasing temperature, reaching a value of 79°, at a temperature of 1100°C, but not sufficient to completely wet the ceramic. However, compatible chemical composition and reduction of porosity by the flow of soft glass waste between the clay particles favor the consolidation of the ceramics structure above 900°C.

Jan 1, 2015

By K. C. Lahiri, H. P. Das, G. G. Sarkar

"The petrographic components of any particular rank of coal often show some distinct physical and chemical characteristics. Therefore, their pro-portionate distribution in a coal greatly influences the technological behaviour of the coal.In any size or gravity separation of a coal, the petrographic constituents become segregated to different degrees in some preferred size or specific gravity range. Therefore, a knowledge of the petrographic nature of the washed and/or screened fractions is often considered essential in selecting the most efficient method for coal preparation and in exploring the proper evenues for its utilization.A graphical method is described in this paper to indicate the mineral-matter content and the petrographic components of the washed fractions of a coal at different ash levels of separation in the form of a new washability diagram. This diagram can be conveniently used to assess or predict the petrographic composition of clean coal or sinks corresponding to any desired ash level in the cleans. With the help of this diagram, it is also possible to locate the yield level of cleans at which maximum enrichment of vitrinites and exinites occurs with the least amount of mineral-matter content."

Jan 1, 1971

Indiscriminate surface disposal of coal waste in New South Wales has created a serious fire hazard and increased air pollution.A survey of numerous dumps, as well as particular investigations of one badly-constructed dump, showed that factors conducive to ignition and propagation of fires in waste dumps were high contents of combustible material (coal, pyrite, wood. paper. grease), size segregation leading to ready movement of air and moisture shape of the dump (e.g. protruding sections or porous junctions), high ambient air temperatures, bush fires, and even deliberate lighting.Control methods applied in the past tended to be haphazard and unsuccessful. Under Australian conditions the technique recommended for control of existing dump fires, based on experimental work, is to spray the dump with a chemical fire retardant (e.g. a 2 per cent solution of sodium tetra borate and ammonium phosphate), to cover the dump with a suitable soil, and to seal the surface with a I per cent solution of aluminium sulphate or sodium metasilicate. The recommended method of dump construction to prevent fires is to level and seal the site, to construct a firebreak around the dump area, and to build a rectangular dump with minimum size segregation and compacted surfaces.

Jan 1, 1971

By Yanan Zhang, Hongwei Deng, Feng Gao, Bo Ke

Recently, liquid carbon dioxide (L-CO2) blasting technology has attracted attention due to its good fracturing effect and safety performance, especially in coal seam permeability improvement. This paper analyzes the blasting effect of L-CO2 based on experiments and studies the fracturing mechanism from the perspective of stress wave action via theoretical analysis and peridynamic simulations. The results indicate that L-CO2 blasting achieves a good fracturing effect without forming a crush zone, and the loading rate and strength of the stress wave are key factors.

Jan 19, 2022

By Julio C. Martinez, Jeffrey L. Rice, Hayden Weschler

This paper details the extensive underpinning required to hold up the 39th street Bridge while demolishing its massive support piers and building a 30ft deep Cut/ Cover RR tunnel beneath it. The underpinning/SOE support required the construction of 16 large hand dug pits 36ft deep that were reinforced and concrete filled. In addition, an extensive steel support system was tied into the bridge super structure. All of the underpinning/tunnel construction was done while a 110ton crane sat directly atop the heavily trafficked – 66 ft. wide bridge. The tunnel excavation, concrete lining and final bridge pier support work will also be presented. All work was done within 5ft of active mainline tracks and that required tight grouting behind all lagging to eliminate any track settlement.

Jun 13, 2021

By Thomas Fraser

"El siguiente estudio señala las recomendaciones para la preparación de las antracitas del Santa de la mina ""La Limeña"", así como las modalidades para determinar los efectos de la ""trituración"" diferencial y ""maceración"" en agua del carbón del tipo ""Limeña"". El resultado de estas pruebas en Bradford, mostraron que el carbón de ""La Limeña"" es adaptable para la ""trituración"" diferencial. Dicho mineral es mucho más blando que el relave, de allí que una gran proporción del carbón limpio disponible permanezca en su tamaño lógico inferior a 5/16"" producido en la extracción y manipuleo. Así también el tratamiento experimental de los tamaños mayores en una planta del tipo Bradford se divide en dos: el primero refiere un relave ""duro "" de tamaño mayor, que contiene una pequeña cantidad de carbón limpio, brillante y fácilmenteescogido a mano; y lo segundo, es una mezcla de tamaño inferior, de ""middling"" y carbón para lavado posterior."

Jul 20, 1955

By M. W. Von Bernewitz

AN important regional meeting of the American Institute of Mining and Metallurgical Engineers was held, at Salt Lake City on Aug. 22 to 26, jointly with the fifth annual meeting of the Western Division of the American Mining Congress. The whole meeting was marked by enthusiasm, keen attention to the subjects under discussion, and many renewals of personal contacts. The trips to the various plants were well attended and the local press paid much attention to the meeting. The A. I. M. E. sessions began Aug. 23, with a non-technical morning session. J. 0. Elton, manager for the International Smelting Co., presided. The purpose of this session was to present in a non-technical manner the relation of flotation to mining, smelting, and the State. Ernest Gayford, metallurgist with the General En-gineering Co. of Salt Lake City, gave the definitions of flotation as suggested by Rickard, the dictionary, Weinig, and Taggart. The active agent in flotation is the air bubble, and the two prime requisites are the formation of bubbles and the creation of selective action of the bubbles for metallic particles instead of for gangue particles. Broadly, all the sulfides are floatable minerals, but the oxides, carbonates, silicates and sulfates are not. As far as Utah is concerned, flotation has been one of the greatest means of conserving its natural re-sources, because it has converted millions of tons of waste rock into pay ore; it is recovering millions of pounds of metal formerly lost in tailings; it has con-verted the zinc from a liability into an asset; and has kept thousands of men at work and distributed millions in dividends for the benefit of the State. As to the future of flotation, Mr. Gayford can con-ceive that the next 5 or 10 years may see as much, if not more, advance than was made in the preceding period. The big problem is dressing oxides, carbonates, silicates, and sulfates, and simplification of the number of reagents, also the separation of different gangue min-erals from one another.

Jan 10, 1927

By S Goff

The Northern Sewerage Project (NSP) is a $650 M infrastructure project that will increase the capacity of the sewerage system for Melbourne’s growing northern suburbs while also helping to protect the Merri and Moonee Ponds creeks by significantly reducing the number of sewage overflows that can occur after heavy rainfall. The NSP consists of two stages: Stage 1 (NSP1) will be owned and operated by Melbourne Water Corporation, and Stage 2 (NSP2) will be owned by Yarra Valley Water and operated by Melbourne Water Corporation.Glass-fibre reinforced plastic (GRP) was used on both NSP stages, however, since Stage 1’s schedule for installation of GRP was slightly ahead of Stage 2’s, this paper will only focus on Stage 1’s use of GRP.NSP1 involves the construction of 7.9 km of new sewer tunnel ranging in diameter from 1.6 to 2.5 m, five main access shafts at depths of up to 65 m, and connections to the existing sewerage system including several access manholes. Construction began in 2007, and project completion is expected in 2012.The original design for NSP1 specified the use of high-density polyethylene (HDPE-) line precast concrete pipes as the final tunnel lining and HDPE-lined reinforced concrete for the access shafts and manholes. During construction, the rising cost of precast concrete pipes and the introduction of an additional GRP pipe supplier in the market justified a review of the tunnel final lining material. The contractor-proposed GRP pipe alternative was accepted for the final tunnel lining based on time and cost savings that were possible without compromising the design intent. After gaining experience with GRP through this design change, Melbourne Water Corporation reviewed and accepted GRP as the final lining for five smaller connection manholes. The use of GRP for the manholes was particularly inventive as the redesign made use of the approved tunnel GRP pipes as both a structural and corrosion-resistant lining.This paper discusses the use of GRP on NSP1; how the change in material, from concrete to GRP, affected the design philosophies assumed during detailed design; and how construction methods were modified to handle the less rigid GRP material. Details on the structural, hydraulic and durability considerations for the design are included, as are details about the time and cost savings and the quality and safety improvements that were achieved during construction.

Mar 8, 2011

By W. M. Mark

This investigation was undertaken to develop methods to improve the quality of titanium sponge produced by the Bureau of Mines modification of the Kroll magnesium reduction process. Research revealed that by systematic elimination of detrimental impurities introduced with the raw materials and by improved handling and processing techniques, high-quality ductile titanium with a hardness of less than 110 B.h.n. (Brinell hardness number) can be produced consistently. This improvement was accomplished by helium (or argon) stripping of residual atmospheric and other dissolved gases from the titanic chloride, preliminary dehydration of crude titanium sponge, and careful regulation of the titanium tetrachloride (TiC14) feed rate to the reactors.

Jan 1, 1960

Book review Proceedings of the Symposium on Mining Methods. London, Institution of Mining and Metallurgy, 1974. 160 pp. The Symposium was held from 30th October to 1st November, 1974, and the papers include an interesting range of subjects in coal-mining operations, covering the improvements achieved to date, current practice, and required development for the future. Salamon, M.D.G., and Oravecz, K. 1. Rock Mechanics in Coal Mining. 119 pp. NIM reports Report no. 1822 Stability constants and linear free-energy relations for the platimtm-group metals. (22nd Oct., 1976). Report no. 1852 A revised method for the dissolution of platiniferous materials by the sealed-tube technique. (18th Oct., 1976). Report no. 1828 y-picoline adducts of the nickel, copper, and zinc chelates of 2-thenoyltrifluoroacetone. (26th Nov., 1976) Report no. 1847 A pilot-plant investigation of a kinetic model for flotation.(19th Nov., 1976)

Jan 2, 1977

By W. Mostowitsh

I. Introductory LEAD sulphate occurs as anglesite, and is formed in every roasting of lead sulphides or sulpho-salts containing lead. In smelting in the blast furnace an ore containing natural or artificial lead sulphate, a large part of the sulphur present goes to the formation of the intermediary product matte which requires further treatment for the recovery of the values it contains. It is therefore of importance to study the behavior of lead sulphate at elevated temperatures, both without and with reducing agents, especially as the information available gives data which are more or less conflicting. II. Decomposition of Lead Sulphate by Heat The dissociation of PbSO4 into PbO and S03 or S02 and 0 has been discussed by many metallurgists. The following data are considered to be representative. Doeltz and Graumann1 found that PbSO4 was not affected by heat at 800° C.; that dissociation began at 900° C., and was rapid at 1,000° when the salt lost in 1 ½ hr. 14.3 per cent. of its weight, the dry salt containing 26.43 per cent. SO3. Hofman and Wanjukow2 summarize their work upon the dissociation of metallic sulphates with the statement that the decomposition of PbSO4 begins at 195° C., but progresses very slowly, with the formation of the basic salt 6PbO.5S03 at 705°; that this salt undergoes a transformation at 847°, begins to be decomposed at 888°, to sinter at 896°, and to fuse at 910°; rapid dissociation begins at 952°, and is accompanied by volatilization of PbO; retardations at 958° and 962° indicate an acceleration of decomposition which, however, is not complete. Proske3 found that PbSO4 gave off at 900° C. in 30 min. only 0.63 per cent. of its SO3, and that the loss increased with

Jan 5, 1916

By J. F. Allan

The main conditions which affect investment in mineral exploration and development are compared in five countries currently considered attractive for mineral investment - Canada, the U.S., Australia, Brazil and the Philippines. The primary parameters - the probability of occurrence and discovery of mineral deposits and the short and long term viability of mineral development - are evaluated and compared on a relative basis by a form of factor analysis. This analysis indicates that of the five countries studied, Canada is second only to the United States in degree of favourability for mineral exploration and development.

Jan 1, 1976

By Nick Vayenas, Ming Cai, Hongbin Zhang Lorrie Fava, Enrique Acuña

"A hybrid methodology is proposed to improve the accuracy of Diesel Particulate Matter (DPM) concentrations simulated in a ventilation network model by using Computational Fluid Dynamics (CFD). DPM, as a primary concern for underground hard-rock mines, has been studied in two dominant numerical models, ventilation network solvers and computational fluid dynamics. Ventilation network solvers are efficient, but they are not able to provide three-dimensional DPM concentration contours and only accept area-average DPM data as input. CFD simulations are time-consuming, but generating DPM concentration results with high accuracy. Besides, both monitoring points and planes can be created in a CFD model, which can take both point data and area-average DPM data as input. The hybrid methodology is intended to combine the advantages of the two by using the CFD results to update the network model results at key locations. A field study was conducted in a dead-end heading in an underground gold mine in the United States. Real-time DPM monitors were used to collect data. A CFD model and a network model were built for the experiment area. The CFD model was calibrated to the experimental data. In the study presented here, results from a calibrated CFD model are converted to equivalent diesel emission rates in the ventilation network model at a shared outlet. The hybrid methodology is used to provide better input for the network model. INTRODUCTION Mine ventilation system is one of the most important parts for an underground mine. It not only provides fresh air to the personnel but also helps clear the contaminants generated from the diesel-powered equipment. For most underground metal and non-metal mines, diesel particulate matter is the main contaminant. It is also the focus of this paper."

Jan 1, 2019

By C. O. Riggs

Geotechnical exploration in North America, in particular, exploration for deep foundations analyses, is currently and generally performed following the most basic sampling and insitu testing methods and techniques. Some would surely say that the state-of-practice severely lags the state-of-the-art. Probably more than 90% of all deep foundations, both driven piles and drilled piers, installed in North America are initially analyzed and designed, i. e. geotechnically, on the basis of either the soil penetration resistance obtained by performing the "Standard Penetration Test" (SPT), or from laboratory shear tests performed on samples obtained using 76-mm (3-in.) nominal diameter, thin wall, "Shelby tube" samplers. The use of design data obtained with other exploration methods and devices, such as bore hole pressure meters, flat plate dilatometers, even cone penetrometers, occur on the fringes of practice and often in conjunction with the use of the two simpler methods of analysis. This basic approach probably represents an attempt of the profession to use, as much as possible, common, easily understood and easily communicated procedures in all geologic environments. The characteristics of drill rigs with the required drilling and samplng tools vary somewhat from region to region in North America according to the physiography of the area of use, the types of exploration data required on a day-to-day basis, the philosophy of the engineers and geologists that use the exploration data and the financial resources of the drill rig owner. The physical capability of the exploration drill rig used on a project can have a significant effect on the quality of samples or insitu tests. The physical configuration and the quality of the drill and the drilling, sampling and testing tools not only provide the mechanical capability to obtain data but affect the attitude of the field exploration crew and the quality of work. This complete presentation is taken, for the most part, from a book in preparation for publication: "Geotechnical Exploration and Site Characterization" by C. Riggs, A. Hatheway and N. Schmidt. The book is scheduled for completion during 1987.

Jan 1, 2010

By Thomas. L. O.

Apart from a few sketches and incomplete maps, mainly topographical, and one or two detailed maps of placer-creeks, there is little information on the topography and geology of most of the country adjacent to the sections of the Alaska Highway in the Liard River area, particularly that part east of Kechika river. In 1943, the Geological Survey of Canada made a recon-naissance from Fort Nelson clown the river of that name to the Liard, thence up the latter to Hell Gate, and also up Beaver river for a distance of fifty miles. The whole of the area covered was found to be underlain by sedimentary rocks, not a single igneous dyke being seen. The British Columbia Department of Mines began reconnaissances near the highway both in and north of the drainage basin of Prophet and Muskwa rivers with a view to finding structures favourable for the accumulation of oil. In Liard River valley near the mouth of Smith river and at intervals from there clown to Devil' s Portage occur warm springs whose character and origin are not definitely' known, since they have not been investigated (21, p. 38A). Similar springs are said to occur at several localities over a broad belt extending from Muskwa river across the Liard to the Nahanni River country (26, p. 11). On Liard river below the mouth of Dease river, stratified sands, gravels, and clays of Pleistocene (?) age are constantly met with and in one or two places are underlain by sandy clays. The distribution of the latter, however, is very limited in the section cut by the river west of the Rocky mountains. The only range of these mountains that reaches the Liard is the high limestone ridge which approaches the mouth of Vents river from the southeast and then almost vanishes a few miles to the northwest of it (27, pp. 43-45). In general, the ranges of the Rockies in the area under consideration have been but little explored, but they are undoubtedly very largely sedimentary and, with the exception of some volcanics and intrusives on their western flanks, are probably almost entirely so. Unlike the high, deeply incised ranges in southern British Columbia, they dwindle in elevation north of Terminus mountain to low-wooded ridges separated by wide swampy valleys, and practically lose their identity between it and the Liard. The foothills, which, along the Liard, have a width of 38 miles (from near the mouth of Trout river to Hell Gate) are composed of a great series of alternating shales and sandstones, with some limestones, all folded closely together, which resemble those found in the foothills farther south (27, pp. 50, 19-20).

Jan 1, 1944

By J. Lindström, J. Hamuyuni, M. Lundström, J. Aromaa

"The rising demand for metals today, coupled with the scarcity of primary sources for raw materials threatens both technological advancements and industrial manufacturing. In order to meet the demand, metals and other resources trapped in waste streams, have to be harnessed. This philosophy supports circular economy, where metals and other resources are kept in a closed loop. The pickling acid recovery system of most stainless steel production is one such example where the dissolved metals such as iron, nickel and chromium are currently not completely recovered due to the limitations of the current technologies. The aim of this study was to assess the available metals recovery methods from extremely concentrated acids. The main aim is to simultaneously recover metals and keep sulphuric acid reusable in acid circulation process. From the available literature, the most promising methods were chosen for laboratory experiments. Based on experimental work, the results and observations of electrodeposition, solvent extraction, and freeze crystallization are provided. KEYWORDS Pickling acid, metal recovery, solvent extraction, cathodic polarization, Freeze crystallization. INTRODUCTION Pickling in stainless steel production is an essential surface treatment process (Regel-Rosocka, M. (2010); Agrawal and Sahu, 2009). It is applied for removing surface films such as oxides and chromium-depleted layers to improve the corrosion resistance and surface finish of steel (Regel-Rosocka, 2010). Whilst the process greatly improves the surface finish of the stainless steel, it generates large amount of used acid, containing dissolved metals including chromium, iron, and nickel (Agrawal and Sahu, 2009). Recovery of acid is common practice for most steel producing industries (Nyman and Koivunen, 1986). In this work, acid regeneration process is investigated so as to simultaneously reusing sulfuric acid and recovering the dissolved metals. Recovery of valuable metals even in very small amounts would also bring additional revenue to the steel production industry. At a time when metal production has also been challenged by lack of natural resources for raw materials, secondary sources for metals such as the acid pickling process therefore, have greater potential as supplements. From earlier studies, electrodeposition (Giovanardi and Orlando, 2011; Kuznetsov et al., 200; Rögener et al., 2012; Surviliene et al., 2006), solvent extraction (Alguacil and López 1996; Haghshenas et al., 2009; Kesieme et al., 2013) and freeze crystallization (Beyer et al.,2003; Hasan et al.,2017; Van der Ham et al., 1999) are some of the most established potential methods. Earlier studies have also shown that simultaneous recovery of acid and metals would require combination of different methods. This is primarily due to the nature of very stable metal containing complex compounds formed during pickling. These complexes must be broken down to free the metals for further recovery processes."

Jan 1, 2018

By J. F. Lewis

Much has been written on this great engineering work, principally from the civil engineer's stand-point. In presenting the subject to the Institute, it seems necessary to include something of geology as well as engineering. In this case, it is particularly the glacial and post-glacial periods with which we are concerned; for it has been clearly proved that the canal recently excavated has not for the first time opened the Des Plaines valley for drainage away from Lake Michigan, and that this valley, as well as the site of this city, is very closely connected with the processes and effects of the ice period. We have simply renewed a channel and a drainage direction which formerly existed. As the days of deep water-ways for commercial purposes are fast approaching, engineers may find the consideration of ancient topography and geologic changes highly useful. For what I may say on this subject I am greatly indebted to Mr. Ossian Guthrie, who has made an earnest study of glacial geology and labored especially to decipher the records of its history in this region. * Chicago is situated in the track of one of four great glacial ice-streams that swept down from the North: one moving due South from Marquette and entering the Illinois valley at Ottawa; one through the Lake Michigan valley, entering the Illinois valley near Lemont; one from Saginaw Bay diagonally across the States of Michigan and Iadiana, entering through

Jan 1, 1898

By S. F. Shaw

Tars paper is a review of the principal details of cyanide practice in several of the modern plants in America, mainly during the year 1908. Two of the mills, the Goldfield Consolidated and the Vets, Colorado, are not yet prepared to give data, the former having started about Jan. 1, 1909, and the latter not yet being completed. These two mills embody most of the latest methods and are therefore described as far as possible. I. CRUSHING. The principal methods of crushing ores for treatment by the cyanide process are with gyratory and jaw-crushers, stamps, Bryan and Huntington mills, and tube-mills. The first stage is usually done by gyratory or jaw-crushers, in a few cases sup-\

Jul 1, 1909

By Y. Kumagai, F. A. Souza

"Electroless plating process has been used in many fields such as automobile and electronic industries. Solutions used in these processes must be disposed or treated. Commonly, in these solutions metal ions, organic materials and others chemicals are in very high concentration. It is very difficult to keep the environmental regulations for disposal of these materials, and the cost of the plating process becomes higher.The objective of this study was to investigate the recovery of components of those baths in order to decrease the cost of the plating process as well as to meet the environmental regulation.In this study the recovery metal ions, sulfate ions, phosphite ions and organic compounds were investigated. Organic compounds used in electroless plating solutions are the organic acids. In this work the solvent extraction of the most used organic acids included citric, lactic, succinic, tartaric and malic was studied. The solvent phase considered in these studies was ethyl acetate.About 95% of the metal ion was recovered by chemical plating onto mica powder. The hypophosphite remained is oxidized to phosphite and with the sulfate ion, both are recovered as calcium salts by selective precipitation in pH 7 and 2 respectively. Organic acids were recovered by solvent extraction using ethyl acetate as solvent phase and the best results were for lactic acid and succinic acid.Along with this study, was developed the analytical parameters to perform wastewater analysis by using Ion Chromatography, High Performance Liquid Chromatography (HPLC), Fourrier Transform Infrared Spectroscopy (FTIR). Ion chromatography was used to perform analysis of sulfate and phosphite ions in liquid matrix, HPLC was used to perform analysis of organic acids in liquid matrix and FTIR was used for characterization of the solids obtained in the recovery processes."

Jan 1, 1997