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By F. E. Block, Stephen D. Hill

The necessity for measuring radiation dose is encountered in studying both the beneficial and damaging effects of ionizing radiation on materials . It is also necessary to know the radiation dose absorbed by the reactants in order to evaluate the efficiency of reactions or processes that are promoted by radiation . Thus , a significant effort was made at the Albany cobalt 60 facility to investigate techniques by which the exposure radiation dose can be determined . Methods including ferrous sulfate , ceric sulfate , and methyl methacrylate chemical dosimeters , ion chamber dosimetry , and an absolute radiation calorimeter were investigated . Isodose curves were constructed for several standard source configurations using the dosimetry techniques which were investigated .

Jan 1, 1964

By Pedro Hugo Tumialán de la Cruz

Dado que el Perú es uno de los países que cuenta con muchos recursos de yacimientos polimetálicos, el presente texto señala los aspectos que comprenden su metalogenia. Dentro de la mineralización de polimetálicos tenemos los siguientes tipos de yacimientos: aquellos relacionados con inyección magmática de composición intermedia a félsica y a la posible inyección de magma ultrabásico, pórfidos de cobre-oro-molibdeno y de cobre-molibdeno, yacimientos de molibdeno, tipo skarn,de reemplazamiento y relleno en caliza, de diseminación de oro de grano muy fino en caliza tipo Carlín, de oro y plata en areniscas-cuarcitas-pizarras, los cordilleranos, de tungsteno, de estaño en intrusivo félsico, volcánicos continentales como los yacimientos filonianos epitermales de plata-oro, los diseminados de oro y plata de baja ley y alta sulfuración, de antimonio, diseminados de oro-plata en intrusivos de composición intermedia, los volcanogénicos marinos de sulfuros masivos tipo Kuroco, tipo Missippi Valley y los lavaderos de oro.Se considerancomo épocas metalogenéticas de estos yacimientos polimetálicos edades de mineralización del Pérmico, Cretáceo Medio, Cretáceo Superior, Paleógeno, Neógeno, Cuaternario.

Jan 1, 2014

By H. Askari-Nasab, S. Upadhyay, A. Moradi-Afrapoli

Material handling in surface mines accounts for around 50% of the operational cost. Optimum truck dispatching plays a critical role in the reduction of this operational cost in truck and shovel surface mines. Researchers in this field have presented several mathematical models to solve the truck dispatching problem optimally. However, a critical survey of the literature has shown that three significant drawbacks exist in the available truck dispatching models. The published models underestimate the importance of the interaction between truck fleet, shovel fleet, and the processing plants. They also disregard goals set by strategic-level plans. Moreover, none of the available models account for the uncertainty associated with the input parameters. In this paper we present a new truck dispatching model that covers all of these drawbacks, using a fuzzy linear programming method. The performance of the developed model was evaluated through implementatin in an active surface mining operation. The results show a significant improvement in production and fleet utilization.

Sep 1, 2021

By Lei Zhang, Shining Chen, Lina Wang, Pu Liu, Benquan Fu, Jiannyang Hwang

A PFS(polymeric ferric sulfate) coagulation-photocatalytic oxidation technology was used for advanced treatment of coking wastewater from secondary biological treatment. Effects of some key factors on TOC removal rate were investigated, and the results were compared with those of the common photocatalytic oxidation technology under the operating parameters of the photocatalytic oxidation defined. Single factor experimental results showed that TOC removal rate could reach 81%, when optimal operating conditions were as follows: TiO2 loading: 4.0g/L, irradiation time: 4h, initial pH is 5.1and PFS dosage:700mg/L. PFS coagulation and photocatalytic oxidation have synergistic effect, which is meaningful for highly efficient treatment of coking wastewater

Jan 1, 2015

By D Wimpenny

The Bogong Power Development Project in Victoria, Australia involved the construction of a 15 m long mass concrete plug up to 9 m in diameter within the head race tunnel. The plug is critical to theperformance of the scheme as it permanently seals the head race tunnel under approximately 300 m head of water.The location of the plug in the headrace tunnel was determined by a programme of in situ rock stress testing using both hydrofracturing and over coring stress testing methods.In recognition of the importance of the plug, the Head Contract specification requires that its temperature during hydration be controlled using an embedded cooling system. In addition, contact grouting and curtain grouting around the plug cannot commence until thermal contraction was substantially complete.This paper describes the use of bespoke fi nite element software to model the temperature rise in the plug and design mitigation measures to control temperature rise in the plug. These measures include restricting the concrete placing temperature to 10°C, incorporating 39 per cent fly ash in the concrete and installing embedded cooling circuits.Site trials were undertaken to calibrate the model for the proposed concrete mix. The cooling system comprised 25 mm ID pipes forming twelve separate circuits that fed 7°C water from a single chiller unit. The cooling system reduced the peak temperature in the plug to approximately 30°C and the associated risk of early-cracking. The time before contact grouting could commence was shortened to less than two weeks from casting.

Mar 8, 2011

By M. H. Dehghanpoor, M. Zivdar, M. Torabi

"A hydrometallurgical route was developed to extract metals such as gold, silver, copper, and selenium from anode slime from Sarcheshmeh Copper Complex in Iran. For the extraction of copper by leaching, the anode slime was heated and stirred with 4 M sulphuric acid in the presence of oxygen. Optimal conditions for recovery of copper were temperature 80°C, mixing time 5 hours, and oxygen flow rate 2 L/min, resulting in a copper recovery of 94.47%. Silver and selenium were dissolved by leaching anode slime from which the copper had been removed with nitric acid. For gold extraction, anode slime was heated with aqua regia at 90°, and the gold then extracted with 2-ethyl-hexanol at a concentration of 0.5 M and phase ratio of 4. The extract was then stripped with soda solution at pH=10.5 and a phase ratio of 5. Finally, gold was recovered by precipitation with oxalic acid at a ratio of mass to volume 10 g/L. Total gold recovery was 80%. IntroductionDuring the electrorefining of copper, some metals are accumulated in the byproduct anode slime, which is an important source for recycling and recovery of these metals (Petkova, 1994). In this paper, a hydrometallurgical route is described for the recovery of precious metals from copper anode slime of Sarcheshmeh Copper Complex, which is located in southeastern Iran .Copper anode slime is black or gray powder with a particle size less than 200 mesh. Approximately 2 to 20 kg of anode slime is produced per ton of copper cathode. The slime is characterized by higher amount of Ag, Se, Pb, and Cu compared to other metals and a very low Au content (Khaleghi and Ghader, 2013).The copper anode slimes are composed of 11.69% selenium, 3.93% copper, 5.26% silver, 0.13% gold, and 45% barite, plus lead, tellurium, antimony, sulphur, and silica with small amounts of nickel, iron, zinc, and bismuth. Gold is one of the most important noble metals due to its wide applications in industry and economic importance, so recovery of gold from slime is more appealing than that of other metals. According to the World Gold Council (2013), the demand for gold has increased during the last decade. This increase is due not only to the increasing demands of the jewellery market, but also to the increasing demand for gold in industrial as well as medical applications (Ranjbar et al., 2014)."

Jan 1, 2016

By E. H. Henderson

Introduction Stamp-Milling and amalgamation is, perhaps, one of the oldest processes of recovering gold from its ores. Many papers, theses, and textbooks have been written on the subject of stamp-milling practice in general, but, to my knowledge, there have been no publications describing the modern stamp-mill as designed, developed, and operated in Nova Scotia. Although it may be said that the gravity stamp-mill is the most primitive, and perhaps the crudest, crushing machine in existence, it is at the same time the most satisfactory all-round milling and amalgamating device yet contrived. Originating in Saxony, and used in North America first in Virginia and Georgia, the stamp-mill, in a primitive form, later found its way to California and Colorado. Here, it speedily developed from an affair of wood shod with iron, and operated with the crudest gearing, to substantially its present form. Briefly, it consists (see Figure 1) essentially of a series of hammers (the stamps), which fall upon a mixture of ore and water contained in a cast-iron box (the mortar). The resulting crushed ore (the pulp) is splashed out through a screen on the front of the box. For some years after the discovery of gold in Nova Scotia, in 1861, the ? arrastra and Chilean mill were used to recover the gold from the rich ores. The stamp-mill followed, and various types were used, principally the California and Gilpin County types. Then, in 1895, Mr. M. R. O'Shaughnessy, one of our foremost amalgamators, conceived the idea of a new type of stampmill, which has since become standard in Nova Scotia gold mines. This mill, unique in its design and operation, is specially adapted for the most efficient extraction and recovery of gold as it occurs in our Nova Scotian ores. It is commonly known as the Underwater Feed type, as opposed to the usual Overwater or Top Feed type, and it may be rightly termed The Nova Scotia Self-Classifying Stamp Amalgamation Mill. It is conceded by experienced mill-men that it is superior to any other type of mill for recovering the very coarse and granular gold typical of the ores of this Province. The particular installation and practice to be described in this paper is that of the Guysborough Mines, Limited, at Goldenville, Guysborough county. Emphasis will be laid on certain operating innovations of extreme simplicity and high efficiency.

Jan 1, 1935

By F K. Altuntov

The study presented in this paper is based on the Kiirunavaara underground mine located in the northern part of Sweden. The deposit is mined using the sublevel caving (SLC) mining method. This paper briefly reviews the alternative SLC layouts, as well as presents challenges for the application. In Kiirunavaara currently, the traditional SLC design is employed, however, continuous improvement of material transportation systems used in mines generates a need for investigation of the current and future production area layouts in sublevel caving mines. When identifying the potential benefits of the alternative production area layouts, the production targets and effects must be further investigated to understand the benefits and potential effects. In this study, several different layouts have been investigated and evaluated. The designs include different development configurations and orepass infrastructure moved further away from the orebody and still require further investigation.

Mar 29, 2023

By Padmavathi V, M. Najamuddin, M. R. Madhav

Granular piles are one of the leading ground improvement techniques, adopted for the betterment of bearing capacity and reduction in settlements of the foundations and also to accelerate consolidation of the surrounding soil. In the recent past, there has been extensive research on the settlement analysis and behavior of granular piles under varied soil conditions. The application of these theoretical solutions to practical problems requires a knowledge of representative values of the deformation parameters of the ground and the granular piles. However, very little information is available on these parameters. The paper presents a new method for the estimation of the modular ratio of granular piles and modulus of deformation of the surrounding in-situ soil from the compression load tests. The load - settlement response obtained from the compression test results are used in the back analysis for estimating the modulus of deformation of the ground. The presence of granular bed, under the rigid plate for load testing, has been given due consideration in quantifying the proportion of load transferred on to the stone column. Based on these considerations a new method is developed to estimate the modulus of deformation of the ground and the modular ratio of the granular pile.

Sep 1, 2022

By Jennifer L. Bell, PATRICK L. YORIO, Emily J. Haas, Susan M. Moore, Lee A. Greenawald

Although researchers have struggled to replicate Heinrich’s safety triangle findings (Heinrich 1931) for various reasons (e.g., no access to his original database and it is unclear if the database was of a single establishment/operation or for an entire industry), the occupational safety community has continued to adopt and expand the applications of this theory (e.g., McSween 2003). Within the mining industry, the potential exists for operations and companies to use concepts from the safety triangle as a way to inform or challenge the practices employed within their health and safety management systems (HSMS) to prevent incidents (Backlund 2016). This paper considers data obtained from the Mine Safety and Health Administration’s databases and demonstrates the validity of applying the safety triangle theory at the mine level. The results support the use of this theory and demonstrate that lower severity incidents can predict fatalities in a subsequent year where significant nuances and caveats to applying the theory are identified and discussed.

Jul 25, 2020

By Ricardo Montero

At this time, over 300 tons of Au are used in electronic equipment each year with other precious and strategic metals such as Ag, Pt, Pd, Cu, Nb, Ta, etc. After the use-phase, the electronic devices become electronic waste (e-waste); consequently it is important to consider e-waste as a secondary supply for recovery of these metals. One of the most important components is the printed circuit boards (PCBs) because the amount of their precious metals is ten times higher than rich precious metals bearing ore. This paper presents the recovery of Au, Ag, Cu and Nb from PCBs of discarded computers using leaching column technique. The amount of these metals in used PCBs was: 613 g/ton of Au, 1515 g/ton of Ag, 36 g/ton of Nb and 23.4 % of Cu. The PCBs were crushed with a hammer mill until reaching a particle size between 3.33 mm to 0.43 mm. Then, it was leached with sodium cyanide solution in a glass column using the following conditions: sodium cyanide concentration 4 g/L, flux 20 L/kg PCBs day, pH between 10.5 to 11 and leaching time 15 days. Every day, after leaching, the pregnant solutions passed through a column with activated carbon to complete the closed loop system. The following recoveries were obtained: 46.6% of Au, 51.3% of Ag, 47.2% of Nb and 62.3 % of Cu. The products obtained are: a) loaded carbon that contains the desired metals and b) processed PCBs with precious metal contents. A preliminary technical-economic study shows the feasibility to create a small-scale PCBs recycling plant. The initial investment is on the order of US$ 155 639, considering the recovered metals from loaded carbon. The internal rate of return for 10 years period (IRR) and net present value (NPV) estimated are 27% and US$ 105 926 respectively. Keywords: printed circuit boards, recovery, precious metals, niobium, leaching column

Sep 1, 2012

By C. T. Shaw

Fur a secure mineral supply position to be maintained in the Fiuropean Community there must be a supply of qualified people in the minerals industries. The education of the people required to run and develop these industries should be a priority in the community. This means that there should be a strong capability in mining engineering education. The mining engineering professors decided in 1990 to get together in a new Society to discuss the problems. The Society of Mining Professors/Societat der Berg-baukunde was formed at a meeting in Austria in October 1990. It is basically a F.uropean Society with a few member professors from outside Europe to keep the Society conversant with trends elsewhere. The objectives of the Society are to see that the mining universities in Fiurope maintain standards and produce enough mining engineers. The present membership of the Society and the work of developing a database of current courses is described. Working from the knowledge base developed, it will be possible to design a 'European' mining degree course. The problems which will have to be addressed have been identified and are described in detail.The paper finally goes on to discuss the other problems that universities are facing, the economic problems and above all the lack of students applying for mining courses across Europe. The help and active participation of the mining industry, if that industry still wishes to employ mining engineers, is identified as the only possible solution to those problems.

Jan 1, 1993

By R. Pandher, R. Schonewille, N. Tripathi

Advanced process modelling tools were developed for the Xstrata Nickel Sudbury Smelter flow sheet using a combination of FACTSAGE TM METSIMTM and ARENATM software. These tools were employed to assist with plant optimisation, emission control, process design, troubleshooting and case studies as applied to the smelter. The development of process modelling tools in pyro-metallurgy commonly involves an in-depth study of the therm o-chemical properties (heat capacity, liquidus temperature, etc.) of all high temperature phases, usually matte and slag. The preferred tool for this purpose is FACTSAGETM, a well-known then-no-chemical modelling software package. The results from the therm o-chemical model have been subsequently incorporated into the development of a process model for the entire smelting facility using the METSIMTM platform. Such process model also includes a number of special features adopted to effectively simulate the complex industrial phases; matte and slag systems. To ensure the robustness and reliability of the process model, several process parameters and assumptions were verified with laboratory and plant data. Consequently, the model includes the ability to examine the impact of a number of plant parameters on potential plant performance. Primary variables are the percent sulphur elimination during concentrate roasting, furnace matte grade and degree of matte metallization. Key output parameters include operating temperature, furnace coke requirement, sulphuric acid production, CO2 emissions and overall energy requirements. Selected outputs from the process model (for example blowing time, slag production rate and matte converting rate) can then be utilised in the development of a discrete event model (DEM) for the smelter using ARENATM software. Incorporation of reliable and validated mass balance parameters enhances the robustness and reliability of the DEM model. The integration of then-no-chemical, process and DEM modeling tools has a distinct advantage in planning plant trials and examining process design initiatives at Xstrata Nickel's Sudbury Smelter. The present paper discusses the development of these three models and the synergies existing among them. Typical results from all three models are also presented.

Jan 1, 2011

By R. Pandher, R. Schonewille

Advanced process modelling tools were developed for the Xstrata Nickel Sudbury Smelter flow sheet using a combination of FACTSAGETH METSIMTM and ARENATM software. These tools were employed to assist with plant optimisation, emission control, process design, troubleshooting and case studies as applied to the smelter. The development of process modelling tools in pyro-metallurgy commonly involves an in-depth study of the therm o-chemical properties (heat capacity, liquidus temperature, etc.) of all high temperature phases, usually matte and slag. The preferred tool for this purpose is FACTSAGETM, a well-known then-no-chemical modelling software package. The results from the therm o-chemical model have been subsequently incorporated into the development of a process model for the entire smelting facility using the METSIMTM platform. Such process model also includes a number of special features adopted to effectively simulate the complex industrial phases; matte and slag systems. To ensure the robustness and reliability of the process model, several process parameters and assumptions were verified with laboratory and plant data. Consequently, the model includes the ability to examine the impact of a number of plant parameters on potential plant performance. Primary variables are the percent sulphur elimination during concentrate roasting, furnace matte grade and degree of matte metallization. Key output parameters include operating temperature, furnace coke requirement, sulphuric acid production, CO2 emissions and overall energy requirements. Selected outputs from the process model (for example blowing time, slag production rate and matte converting rate) can then be utilised in the development of a discrete event model (DEM) for the smelter using ARENATM software. Incorporation of reliable and validated mass balance parameters enhances the robustness and reliability of the DEM model. The integration of then-no-chemical, process and DEM modeling tools has a distinct advantage in planning plant trials and examining process design initiatives at Xstrata Nickel's Sudbury Smelter. The present paper discusses the development of these three models and the synergies existing among them. Typical results from all three models are also presented.

Jan 1, 2011

By Arman Ehsani, Ersin Yazici, Haci Deveci

The downstream treatment of chloride leach solutions of WPCB for recovery of base and precious metals by a combination of adsorption and precipitation processes were carried out. A synthetic leach solution (1 M HCl, 116.5 g/L Cl-, 30 g/L Cu2+, 2.5 g/L Fe3+, 5 mg/L Au3+, 10 mg/L Ag+ and 20 mg/L Pd2+), which was prepared based on the composition of the pregnant leach solution obtained in the previous study was used in the tests. The leach solution was initially subjected to activated carbon (AC) adsorption (20 g/L AC, 80°C) in which gold was selectively recovered over silver and palladium i.e., 88% Au recovery at 0.5 h (92% at 3.5 h) compared with only 3-6% for Ag/Pd. Copper and iron were also observed to adsorb on AC as indicated by 1.4% and 17% decline, in their respective concentrations. Following the adsorption and filtration stage, metallic copper was added into the gold-barren solution to allow reduction of Cu2+ to Cu+, and to cement Pd on metallic copper. Over the mixing period (1 h), 93% of the Pd was recovered while only 1.4% of silver was cemented onto metallic copper. Subsequently, the leach solution was gradually neutralised by NaOH to pH 4, 7.5 and 9.5 for the precipitation of copper as cuprite (Cu2O). It was found that 41% and 46% of Cu and Ag, respectively, were precipitated at pH 4 at which iron was almost totally (99.8%) removed from solution. Precipitation of copper and silver was increased further at high pHs. At pH 9.5, cumulative recoveries for copper and silver were 91% and 85%, respectively. XRD analysis of the precipitates confirmed the presence of cupric copper oxides/hydroxides and revealed that copper losses occurred at pH 4 was due to the undesired presence of cupric copper in the solution.

Jan 1, 2014

By Tilman M. M.

The effects of substituting cobalt for nickel on the acid corrosion resistance of two types of austenitic stainless steel were determined. Cobalt substitutions to a maximum 2.2 weight-percent were made in types 302 and 309 stainless steels. Total immersion corrosion tests were made in 10 volume-percent hydrochloric acid, and boiling-acid tests were conducted in 65 weight-percent nitric acid and in undiluted glacial acetic acid. For modified type 309 in acetic acid, corrosion rates decreased for additions greater than 0.57 weight-percent cobalt. Corrosion rates increased as cobalt was increased up to about 1 weight percent for modified type 302 in nitric and hydrochloric acids and for modified type 309 in nitric acid, but these rates decreased with a further increase in cobalt content. A gradual increase in corrosion rates with increasing cobalt content was shown for type 302 in acetic acid and for type 309 in hydrochloric acid. Cobalt substitutions in larger amounts (above a ratio of 8 Ni to 1 Co) may increase the corrosion resistance of the austenitic stainless steels.

Jan 1, 1965

By Kenji Sasaki

Tamano Smelter started its operation in January, 1972 adopting FSFE ( Flash Smelting Furnace with Furnace Electrodes ) type smelting furnace at a production capacity of 101,00Ot/y of anode copper and 285,00Ot/y of sulfuric acid. Since then, it had experienced several production expansion program, it had twice as production capacity as start. 196,000t/y of anode copper and 436.000t/y of sulfuric acid. This time, we have completed the plan for increasing production capacity up to 226,000t/y of anode copper and 510,000t/y of sulfuric acid, by the oxygen enriched operation. We carried out several improvements and modifications, changing of cooling system ill FSFE, enlargement of converter and anode furnace, and some progresses in sulfuric acid plant and environmental facilities.

Jan 1, 1993

By C. M. Bristow

The mineral kaolinite is one of the commonest minerals in the uppermost 10 m of the continental crust; ranking in abundance alongside minerals like quartz, mica, feldspar and calcite. Only very exceptionally does it possess all the necessary properties needed to make it worth commercially exploiting. The terms 'Kaolin' and 'Kaolinite' are derived from a locality known as 'Kau-ling', in Jiangxi Province, Peoples Republic of China; where samples of a white clay used by the Chinese to make porcelain were first obtained by European missionaries and explorers in the eighteenth century.

Jan 1, 1986

By Patrizia Pereyra, M. Guzman, C. Toledo, J. A. Rau, A. Ruiz

The use of mining tailings-based geopolymer binder as a substitute for cement can be an interesting alternative to the problem of final disposing of large volumes of them. Indeed, mining tailings have a high silica content, which makes them suitable for geopolymerization. The tailings samples contain Cu, Pb, Zn, As, Sb, Cd and Bi, mainly. X-ray diffraction results show that the tailings are composed of quartz, SiO2 (81%). Geopolymerized tailing samples (GTPS) were obtained by varying the ratio of SiO2/ Al2O3 and SiO2/NaOH. The compressive strength of the GTPS varied between 2 MPa and 8 MPa. The electrical conductivity in the leaching tests varies between 13.91– 16.11 mS/cm2 indicating that ions are present in the solution. However, the pH = 10.5 indicates that acidity is not being generated. The element that mostly leaches is iron. The highest percentage of leaching is observed for cadmium (69%) and chromium (93%). The concentrations of elements are under the maximum permissible limits for water according to the Peruvian legislation. However, mass transfer leach tests and immersion leach tests must be realized.

Feb 1, 2024

By R. G. Coyle

"In an earlier paper the author explored the consequences of price-stabilizing effects, on an industry-wide basis, of various production strategies. These ideas have now been applied to an illustrative case of an individual mine. It is shown that the turning of production and financial policies can affect financial performance over a five-year period by as much as 22 per cent.No generality is claimed for the results and they would differ from mine to mine. It is, however, asserted that the results show that the proper turning of production, reserves and financial policies are more critical determinants of mine performance than has been realised. It is also asserted that the methods of dynamic analysis are the most appropriate means for studying this policy-design problem."

Jan 1, 2014