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Dammsäkerhetsutvärdering samt utformning av dammregister och felrapporteringssystem för svenska gruvdammar / Dam Safety Evaluation and Development of a Database for Swedish Tailings DamsIsaksson, Nils, Lundström, Helena January 2005 (has links)
A lot of mine waste rock and tailings arise from all mining processes and have to be stored in an appropriate way. Tailings are deposited in impoundments retained by tailings dams. The objective of tailings dams is to retain the slurry from the mining process and in that way prevent spill into the surroundings that might be harmful for the environment. Tailings dams are often constructed as staged embankments so that construction costs and demand of materials are spread more evenly over the period of deposition. The objective of this thesis has been to compile information about and evaluate events at Swedish tailings dams and also to develop a collective database for all Swedish mining companies for all tailings dams and all events that occur at tailings dams. Information about 60 events at Swedish tailings dams has been gathered and evaluated. The evaluation has been performed by comparison between and analysis of individual parameters and also by use of a multivariate statistical method called PLS. The statistical analysis shows a decrease in the numbers of events during the last five years, which indicates improved dam safety within the mining industry. The analysis also shows that severe events and the human factor might be related when it comes to the initiating cause of the event. Further relations between the parameters and the severity of the events can be seen from the PLS-analysis, for example that low and short tailings dams to a greater extent are subjected to severe events. To be able to draw more reliable conclusions further studies with a more complete basic data are needed. This work has shown a need of a collective database within the Swedish mining industry for tailings dams and occurring events at tailings dams so that more complete basic data could be obtained for future studies. A structure for such a database has been developed in Microsoft Access 2000. The aim of the database is to facilitate feedback within the mining industry and to gather comprehensive data for future statistical evaluations. / Vid alla gruvprocesser skapas stora mängder restprodukter i form av gråberg och anrikningssand som måste tas om hand på lämpligt sätt. Anrikningssanden deponeras tillsammans med vatten från gruvprocessen i magasin omgärdade av dammvallar, s.k. gruvdammar. Gruvdammar har som syfte att hålla kvar anrikningssand och vatten och måste vara stabila så att de skyddar omgivningen från utsläpp av anrikningssand som skulle kunna vara skadligt för miljön. En gruvdamm byggs ofta upp i etapper eftersom byggkostnaderna och behovet av dammfyllnadsmaterial då sprids över tiden. Syftet med arbetet har varit att sammanställa och utvärdera händelser vid svenska gruvdammar samt att utforma ett för gruvindustrin gemensamt dammregister och felrapporteringssystem. 60 händelser vid svenska gruvdammar har sammanställts och utvärderats. Utvärderingen har genomförts dels genom att enskilda parametrar jämförts och analyserats och dels med hjälp av den multivariata analysmetoden PLS. Den statistiska analysen visar på en minskning i antal händelser under de senaste fem åren, vilket tyder på ett förbättrat dammsäkerhetsarbete inom gruvindustrin. Analysen har kunnat uppvisa ett samband mellan allvarliga händelser och den mänskliga faktorn när det gäller vad det är som initierat händelserna. Genom PLS-analysen har ytterligare samband mellan de undersökta parametrarna och allvarlighetsgraden av händelserna kunnat utläsas, bl.a. visar analysen att låga och korta dammar i större utsträckning drabbas av allvarliga händelser jämfört med höga och långa dammar. För att säkra slutsatser ska kunna dras krävs dock vidare studier med ett mer komplett statistiskt underlag. Examensarbetet har påvisat ett behov av ett branchgemensamt damm- och felrapporteringsregister för att ett mer komplett underlag ska kunna erhållas i framtiden. En färdig databasstruktur för ett sådant dammregister och felrapporteringsregister för svenska gruvdammar har utformats. Databasen är uppbyggd i Microsoft Access 2000 och är tänkt att underlätta erfarenhetsåterföring inom branschen samt att ge ett underlag för framtida statistiska undersökningar.
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Automated Extraction and Retrieval of Metadata by Data Mining : a Case Study of Mining Engine for National Land Survey SwedenDong, Zheng January 2010 (has links)
Metadata is the important information describing geographical data resources and their key elements. It is used to guarantee the availability and accessibility of the data. ISO 19115 is a metadata standard for geographical information, making the geographical metadata shareable, retrievable, and understandable at the global level. In order to cope with the massive, high-dimensional and high-diversity nature of geographical data, data mining is an applicable method to discover the metadata. This thesis develops and evaluates an automated mining method for extracting metadata from the data environment on the Local Area Network at the National Land Survey of Sweden (NLS). These metadata are prepared and provided across Europe according to the metadata implementing rules for the Infrastructure for Spatial Information in Europe (INSPIRE). The metadata elements are defined according to the numerical formats of four different data entities: document data, time-series data, webpage data, and spatial data. For evaluating the method for further improvement, a few attributes and corresponding metadata of geographical data files are extracted automatically as metadata record in testing, and arranged in database. Based on the extracted metadata schema, a retrieving functionality is used to find the file containing the keyword of metadata user input. In general, the average success rate of metadata extraction and retrieval is 90.0%. The mining engine is developed in C# programming language on top of the database using SQL Server 2005. Lucene.net is also integrated with Visual Studio 2005 to build an indexing framework for extracting and accessing metadata in database.
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Discussion And Evaluation Of Mining And Environment Laws Of Turkey With Regard To Eu LegislationSafak, Sukru 01 September 2006 (has links) (PDF)
ABSTRACT
DISCUSSION AND EVALUATION OF MINING AND ENVIRONMENT
LAWS OF TURKEY WITH REGARD TO EU LEGISLATION
Turkey is trying to become a member of the European Union. Within this frame,
studies are proceeding for harmonization of the Turkish legislation with the EU
legislation. European legislation might have positive or negative impact on the
mineral extraction industry and national mining law. Since there is no title directly
related to mining policy in the EU legislation the mining policy of EU was evaluated
especially under the titles&ldquo / energy&rdquo / and &ldquo / environment&rdquo / .
In this thesis, the Turkish mining regulations and the environmental aspects of the
mining activities have been investigated and discussed in comparison with those of
EU. The latest developments about mining sectors of Turkey and EU have been
evaluated and the comparison between EU directives and Turkish laws and
regulations about mining have been made.
In this study, modifications that should be realized in laws and regulations and
measures that should be taken by Turkey as a candidate country for EU discussed
and some proposals have been made.
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Hydrometallurgical Extraction Of Nickel And Cobalt From Caldag Lateritic OreOzdemir, Veysel 01 September 2006 (has links) (PDF)
In this study, an attempt has been made to hydrometallurgical extraction of cobalt and nickel by atmospheric pressure sulphuric acid leaching and a pug-roast-leach process using two stage roasting for lateritic ore. The ore used in the study was obtained from Ç / aldag Lateritic Ore, Manisa, Turkey. The metal contents of the ore are 2.1 % Ni, 0.12 % Co, 32.45 % Fe, 1.01 % Mn, 2.58 % Cr, 0.78 % Mg and 1.01 % Al. The reserve of lateritic ore deposit is approximately 40 million tonnes.
In the study, first sulphuric acid leaching was applied at atmospheric pressure for leaching the Ç / aldag lateritic ore. The effect of various parameters, such as leaching time, leaching temperature, particle size, pulp density and acid strength on Ni and Co extractions were determined. By leaching at 80oC for 40 wt % H2SO4 addition of ore, 1/3 pulp density, Ni and Co extractions were found 44.49 % and 53.03 % respectively, yielded a pregnant solution containing 3.11 g/L Ni and 0.12 g/L Co. But the result of atmospheric pressure sulphuric acid leaching was considered insufficient from the recovery point of view.
In the pug-roast-leach process, which is consisted of a two stage roasting followed by water leaching, decomposition temperature differences of sulphates of cobalt, nickel and iron are exploited. In this process, amount of acid, sulphatization and decomposition temperature, sulphatization and decomposition time, leaching temperature and time, solid/liquid ratio, and the effect of water addition during pugging were optimized. Under the optimized conditions (sulphuric acid: 25 wt % of ore / moisture: 20 wt % of ore / sulphatization temperature: 450oC / sulphatization time: 30 minutes / decomposition temperature: 700oC / decomposition time: 60 minutes / leaching temperature: 70oC / leaching time: 30 minutes and solid-liquid ratio: 1/4 by weight), Co and Ni extractions were found 91.4 and 84.4 percent, respectively. A pregnant solution containing 3.084 g/L Ni and 0.185 g/L Co was obtained. These results were considered sufficient for the leaching of lateritic nickel ores.
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Investigation Of The Rheological Properties Of Cayirhan Coal-water MixturesOztoprak, Ayse Feray 01 December 2006 (has links) (PDF)
In this thesis, coal-water mixtures (CWM) with Ç / ayirhan lignite were prepared to optimize the parameters of CWM having an ideal behavior which means that at maximum coal loading, relatively stable at static and dynamic conditions and exhibit low viscosity. For this purpose, the effect of the parameters such as pulp density, amount of chemical agents, particle size distribution, addition of methanol and pulp pH were investigated. Results showed that increasing pulp density negatively affects viscosity and allowable maximum pulp density was obtained as 60% when the particle size distribution has a d50 value of 22.82 µ / m. The optimum amount of chemical agent was found as 0.9%, having 10% Na-CMC (Sodium Carboxymethyl Cellulose) and 90% PSS (Polystyrene Sulfonate). Minimum viscosity was achieved when the pulp pH was in natural conditions (pH=6.85). Addition of methyl alcohol increased the viscosity of CWM.
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An Aproach On Dilution And Ore Recovery/ Loss Calculation In Mineral Reserve Estimations At The Cayeli Mine, TurkeySoyer, Nihat 01 December 2006 (has links) (PDF)
Dilution and ore recovery/loss have an important role in calculation of mineral reserves. Each percent increase in dilution and decrease in recovery negatively affects economic value of the reserve. These parameters are mainly controlled by the quality of the mine design and stoping practice.
This study provides an approach developed for dilution and recovery/ore loss calculations. The contribution of mine design software (MineSight) and the recent survey technique called Cavity Monitoring System (CMS) were presented in this study. The purpose was to compare the new approach with the old system where the calculations had been done according to some assumptions and to optimize mineral reserve estimation process.
Results indicate that the new approach used in reserve estimation process gives ~1.6% closer tonnages to the actual numbers and the grades are both ~1.6% closer to the actual values numbers when compared with the old system.
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Use Of Aluminium Dross For Slag Treatment In Secondary Steelmaking To Decrease Amount Of Reducible Oxides In Ladle FurnaceAydemir, Onur 01 January 2007 (has links) (PDF)
In this study it was aimed to analyse refining processes such as decreasing
reducible oxide content of ladle slag with affecting parameters in low carbon
aluminum killed grades and for the research Erdemir low carbon steel grades 7112K
and 7110K are selected. There was a negative correlation between reducible oxide
amount in ladle slag and desulphurization capacity of ladle slag with metal-slag
reaction and steel internal cleanliness. To refine these properties of slag, aluminium
dross, which was aluminium production discard and has a metallic content around
%30-35 was used and after ladle treatment operation, decrease in reducible oxides
such as FetO, MnO, SiO2, P2O5 was analysed. After the study it was observed that
653 kg. of converter slag leaked during tapping of steel and SiO2 ve P2O5 content of
ladle slag had negligible change after ladle treatment. According to the results, it is
observed that initial %10-12 (FetO + MnO) content was reduced to % 4.5-5.0 (FetO
+ MnO) after ladle treatment with use of aluminium dross. Beside of this, in order to
see the effect of this slag reduction on steel cleanliness, low carbon aluminium killed
grades were compared with ultra-low carbon aluminium killed grades having (FetO +
MnO) content of %16-17 in slag. It was seen that reoxidation of aluminium (loss of
dissolved aluminium) during continuous casting for ULC (ultra-low carbon) gradesis 144 ppm but for LC grades it was 94 ppm and it was being expected that ULC
steel group would have higher inclusion content after casting.
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Use Of Borates As An Activating Agent For Drilling Mud BentonitesToka, Bulent 01 March 2009 (has links) (PDF)
In drilling technologies, Na-bentonite-water mixtures are used as drilling mud. As the reserves of sodium-bentonite decline, calcium or low-quality bentonites are activated with inorganic salts and/or treated with different types of polymers as an alternative to Na-bentonite. The quality of such bentonites, commonly referred to as extended bentonite may deteriorate under severe drilling conditions, such as / bacterial activity, high temperature etc. It was considered that borates could prevent the deterioration of extended bentonites due to their well known bactericide properties. This study involves the use of Na-Borate as an activating agent for bentonites in place of the commonly used Na-carbonate.
The effects of Na-borate on the rheological and filtrate behaviours of two different bentonites, namely, Edirne Bentonite (E-Ben) and Ç / ankiri Bentonite (C-Ben) were investigated. The results were evaluated based on API standards and in comparison to those of Na-carbonate activated bentonites.
It was found that Na-borate could be used as a bentonite activator, although somewhat higher dosages (3,78% Na2O equivalent for E-Ben and 0,76% Na2O equivalent for C-Ben) than Na-carbonate (2,90% Na2O equivalent for E-Ben and 0,58% Na2O equivalent for C-Ben) are necessary to obtain the same rheological properties. In terms of aging, it was determined that aging had no adverse effect on
v
the rheological and filtrate properties of bentonite treated with carboxymethyl cellulose (CMC) and polyanionic cellulose (PAC), but rheological properties of bentonites treated with xanthan gum were found to deteriorate upon aging. The presence of Na-borate in the mud appears to alleviate this adverse effect.
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Computer Modeling Of The Initial Cavern For Beypazari Trona Ore On The Basis Of Leaching Rates, Insoluble Contents And Thickness Of Trona LayerTuncay Saygun, Ilkay 01 March 2008 (has links) (PDF)
Trona ore located in Beypazari is extracted by solution mining method with well pair connected by directional drilling technology. This thesis covers the determination of the dimensions of the initial (vertical) caverns formed in underground by use of a computer modeling (trademark: WinUbro/Poland) on the basis of horizontal and vertical leaching rates. The leaching rates were determined using the trona core samples from the ore deposit. The effect of insoluble content and the thickness of trona layer and solvent temperature on the initial cavern dimension were studied. The outcome of this study showed that the better the trona layer quality from the point of view of thickness and insoluble content, the wider the vertical cavern size is. In 1 m thick trona layer with 20% insolubles, it is possible to develop caverns of 6 m width, which is the minimum size for well pair connection. On the other hand, it is determined that the effective leaching time depends mainly on solvent temperature.
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An Investigation Of The Principles Of Laboratory-scale Particle-bed ComminutionCimilli, Hande 01 May 2008 (has links) (PDF)
The objective of this thesis is to investigate the principles of laboratory-scale particle bed comminution in a piston-die-press. The feed materials used in this investigation are quartz and calcite which were stage-crushed and dry screened to produce 3.35 x 2.36, 2.36 x 1.7, 1.7 x 1.18, 1.18 x 0.85, and minus 0.85mm size fractions. First, these narrow size fractions (excluding minus 0.85mm fraction) were comminuted under different pressures to determine the baseline for energy utilization. Then, these size fractions and minus 0.85mm size fraction were proportionately mixed to produce feeds of three different size distributions having three different Gates-Gaudin-Schuhmann (GGS) size distribution moduli (m=0.5, 0.7, and 0.9), and comminuted under different bed pressures of appropriate magnitudes to generate a reasonable range of specific breakage energy inputs.
As a result of the experiments carried out, it can be concluded that higher amounts of fines were obtained from calcite samples than quartz at all narrow-range size fractions and distribution moduli. Furthermore, experimental results showed that the feed material having the widest size distribution (m = 0.5) showed more resistance to size reduction when compared with narrow-size fractions, which led to increase in energy consumption due to the presence of higher amounts of fines. Tests samples with distribution moduli of 0.7 and 0.9 showed higher resistance to size reduction than narrow-size samples, but the reduction ratios achieved with the size distributed samples were higher than those achieved with the narrow-size samples. In addition, by using t-curves (t50 and t10) the amounts of breakage of different samples were compared. Consequently, the distribution modulus of 0.9 gave better breakage results in terms of expended energy and amount of breakage than all narrow-size fractions, especially for the relatively soft mineral calcite.
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