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Simulación del uso de stockpiles diferenciados para la implementación de gestión de demanda energética en molienda SAGAlarcón Solís, Héctor Ignacio January 2019 (has links)
Memoria para optar al título de Ingeniero Civil de Minas / A lo largo de los años la minería ha incrementado sus costos en energía eléctrica, por lo que ha sido necesario trabajar con energías renovables para amenizar este impacto, por esta razón la implementación de paneles fotovoltaicos a la molienda SAG es un proyecto atractivo y proyectado a la futura minería.
A partir del párrafo anterior, este estudio busca evaluar la implementación de la gestión de demanda en el molino SAG considerando aplicar el mismo sistema en el transporte de mineral desde la mina hasta la zona de stockpiles, el que será diferenciado en dos stockpiles por la dureza diferenciada de mineral y así comprobar si el proceso de DSM es factible, disminuyendo los costos asociados a la operación.
Con los resultados se tiene que al aplicar la gestión de demanda que diferencia el mineral por su característica de dureza, genera una disminución en los costos operacionales para la simulación. A medida que aumenta el plan de producción de la mina, esta entrega un valor de hasta un 13% menor que el caso base (un funcionamiento sin gestión de demanda) para un procesamiento de 9000 tph. Además, el costo operacional es menor en las simulaciones de los casos DSM que presentan una cantidad de mineral diferenciado (alta o baja dureza) que es un 20% de la cantidad total de mineral, generando una diferencia en el costo operacional de hasta un 5%.
Por último, el costo capital del Caso DSM es mayor que para el Caso Base, esto se debe a la incorporación de todo el circuito complementario para la instalación del segundo stockpile que alimenta el mineral diferenciado por la gestión de demanda al molino SAG. Por la información recopilada va a corresponder al 2% aproximadamente.
El costo operacional de la mina es un 90% mayor que el costo del Molino SAG, por lo tanto, al aplicar la gestión de demanda es recomendable ajustar un plan minero que cumpla con la extracción de mineral e incorpore la nueva condición. De esta manera se logre utilizar la gestión de demanda energética y hacer una minería más sustentable con el medio ambiente.
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The Simulation and Analysis of Particle Flow Through an Aggregate StockpileParker, Brian Mark 17 December 2009 (has links)
For many aggregate mining facilities, the stockpile is the preferred method of storing rock. In many aggregate mines, as well as other mines using stockpiling techniques, understanding the timing and flow of particles through a stockpile is important for correctly timing samples, making proper process adjustments and overall stockpile safety. Because much of the research of today lacks important information regarding actual interior particle movement within a stockpile, a series of Real Time Distribution (RTD) analyses and stockpile flow models have been prepared and analyzed for this study in order to better understand the flow characteristics of a stockpile.
A series of three RTD analyses performed on three separate stockpiles provides information leading to the assumption that stockpiles tend to operate similar to a plug flow system. While conveyor loading techniques may lead to separation of rocks prior to traveling through the stockpile, the majority of the rock particles entering the pile remain near the point of entry, or within the "action" area, and will travel through the pile in a plug flow, rather than a mixed flow, manner. High Peclet number results for each analysis prove this assumption to be accurate.
A series of models on three separate stockpiles have been created using PFC3d. Mainly, the simulations prove PFC3d is capable of showing how stockpile particles move in three dimensions while monitoring specific particles within the pile. In addition, these models provide simulation results similar to the results obtained within the RTD analyses. Results show that particles located directly above the discharge point, or "action" area, travel through the pile at a faster rate than particles surrounding this area. Velocity results obtained from the simulations show particles accelerating as they get closer to the discharge points while also providing evidence of "arching" during the simulation process. These findings provide a better understanding of internal flow within the stockpile and ways to possibly predict future stockpile flow issues that may be encountered. / Master of Science
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Evaluation of Unmanned Aerial Vehicle Flight Parameters That Impact Stockpile Volume ComputationsHastings, Nicole Marie 08 December 2023 (has links) (PDF)
Stockpile volumes are monitored by their companies as the product (i.e., aggregate, soil) is moved in and out of the facilities to ensure minimal product loss. Companies are mandated to report product movement to the government to ensure that the aggregate and soil is going where it is supposed to go. Many tools are used to monitor stockpile volumes including truck scales (to weigh incoming and outgoing trucks), light detection and ranging (LiDAR), Global Navigation Satellite System (GNSS) equipment, and unmanned aerial vehicle (UAV) photogrammetry. These processes give a good estimate of stockpile volumes. Errors in these estimates typically come from transportation and natural degradation of the stockpile. Not much research has been done on the best practices when using UAV photogrammetry to find the volume of a stockpile. Most recent research is about specific situations for finding a stockpile volume and whether UAV photogrammetry is as good as traditional methods for finding stockpile's volume. This study focuses on the effect of the flight height, camera angle, and presence of ground control points (GCP) in processing on the final volume calculated. Six UAV flights were done for this study; three different flight heights and two different camera angles. Additionally, the UAV reconstructed models were run with and without the GCPs to give twelve reconstructed volumes to examine for statistically significant differences. A similar study was done by Tucci et. al\cite{Tucci2019} where they focused on only camera orientation and found that the camera orientation was not statistically significant. We found that the differences between if GCPs in processing or not and between each flight elevation was statistically insignificant. We found that the differences in camera orientation between nadir and oblique were statistically significant. These different results could be due to many variables including differences in the dataset, differences in the statistical analysis, or the difference in stockpile size. We recommend using a high flight elevation and oblique photos to develop an efficient, accurate model.
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Characterization of Geochemical and Mineralogical Controls on Metal Mobility in the Prairie Creek Mine Area, NWTSkeries, Kristina 05 July 2013 (has links)
The Prairie Creek Mine, NWT, is a non-producing Zn-Pb-Ag mine located within the Mackenzie Mountains. The 320 km2 area is surrounded by the Nahanni National Park Reserve, and is found approximately 40 km upstream of a UNESCO World Heritage Site. Geochemical characterization of weathered material in the area is useful from both an exploration geochemistry and environmental geochemistry perspective. This investigation attempted to characterize geochemical and mineralogical controls on metal mobility in natural and manufactured environments. Surface waters and sediments were sampled, analyzed, and interpreted. Detailed mineralogical analyses were also performed, including SEM, XRD, and synchrotron-based µXRF and µXRD.
Prairie Creek contains sulphide and supergene mineralization hosted in carbonate rocks, which supply the area with a high pH, as well as a wealth of alkalinity and buffering capacity. This study aims to provide some insight as to the geochemical and mineralogical controls on the weathering processes which may enhance or inhibit mobility of metals downstream of known mineralization. Results show that the metals are found in much higher concentration in the stream sediments than in the stream waters. Pb and Zn show the highest concentrations, and Zn appears to be more mobile than Pb. Based on water versus sediment chemistry, it may be possible to differentiate between mineralization types. Dissolution textures and alteration of detrital grains indicates that chemical weathering does occur within the streams and releases metals to the aqueous environment, though they are likely quickly attenuated through adsorption or co-precipitation.
The mine site hosts a historic ore stockpile and waste rock pile, established in the early 1980’s. Geochemical characterization of the reactions occurring within these piles and of the mineralogical controls on metal mobility can contribute to the mitigation of risk from leachate. Metal concentrations are variable and do not support a trend, which indicates that metal mobility within these piles may be attributed to micro-environments. There appears to be a trend in increasing alkalinity and decreasing sulphate towards the bottom of the piles.
Therefore, metals appear to have limited mobility in the studied environments, although small scale chemical reactions are occurring which may release and attenuate metals. / Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2013-07-04 20:00:21.774
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Assessment of the community healthcare providers' ability and willingness to respond to a bioterrorist attack in FloridaCrane, Jeffrey S 01 June 2005 (has links)
Previous findings have demonstrated that the preparedness and infrastructure of the public health system is inadequately developed for a biological and/or chemical terrorism attack.(1-4) Chen et al. reported that those primary care providers that would have to respond to such an attack do not feel prepared to diagnose and manage such an event.(5)This research was an observational study using e-mail/web based survey to assess the levels of preparedness (PL) and willingness to respond (WTR) to a bioterrorism attack, and identify factors that predict PL and WTR of Florida community healthcare providers. The conceptual framework and questionnaire was designed based on empirical studies and the use of an expert panel to assess the providers administrative and clinical competencies, WTR, and PL. The questionnaire was pilot tested in 30 subjects. Reliability was high (Cronbachs alpha =.82).
The emailed invitaiton letters were sent to 22,800 healthcare providers in Florida. The questionniare was posted for 7 days on the website during December, 2004.There were 2,279 respondents of 9,124 who received the e-mails. Response rate was 28%, with 86% completed questionnaires. The subjects included physicians (n=604), nurses (n=1,152), and pharmacists (n=486). The results demonstrated that only 32% of the Florida providers were competent and willing to respond to a bioterrorism attack. 82.7% of providers were willing to respond in their local community and 53.6% within the State. The subjects were more competent in administrative skills than clinical knowledge (62.8% vs. 45%) The most competent areas were the initiation of the treatment and recognition of their clinical and administrative roles. The least competent areas were identifying the cases and communicate risk to the others.
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Disponibilidade de antídotos para o tratamento de pacientes intoxicados nas unidades de emergência do município de Campinas-SP / Availability of antidotes for treatment of poisoned patients in emergency departments in the municipality of Campinas-SPFernandes, Luciane Cristina Rodrigues, 1980- 25 August 2018 (has links)
Orientador: Fábio Bucaretchi / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-25T19:06:06Z (GMT). No. of bitstreams: 1
Fernandes_LucianeCristinaRodrigues_M.pdf: 3350609 bytes, checksum: 1749edf65ae7946299b707cd046715f2 (MD5)
Previous issue date: 2014 / Resumo: Introdução: A carência de adequada e pronta disponibilidade de antídotos é um problema mundial, com consequências potencialmente desastrosas. Objetivo: Avaliar a disponibilidade de antídotos empregados no tratamento das intoxicações nos serviços de emergência públicos e privados da cidade de Campinas. Métodos: Um questionário estruturado foi encaminhado aos responsáveis por farmácias de serviços de emergência de Campinas-SP, públicos e privados, que compuseram a amostra. A disponibilidade, quantidade estocada, local de estoque, e tempo de acesso na sala de emergência (imediata ou dentro de uma hora) a 31 antídotos em 33 apresentações farmacêuticas foi pesquisada, considerando o estoque de pelo menos um tratamento completo por antídoto por serviço, para um adulto com peso estimado de 70 kg. A seleção dos antídotos se baseou em recomendações de estoque contidas em diretrizes internacionais publicadas até o final de 2009. Não foram incluídos na análise soros antiveneno de animais peçonhentos. Resultados: Os questionários foram completados por 14 de 17 serviços de emergência operantes à época, sendo 7 públicos e 7 privados. Nenhuma unidade de emergência dispunha de todos os 31 antídotos selecionados, e nenhuma dispunha de anticorpos antidigoxina, de fisostigmina, de fomepizole, de hidroxicobalamina ou de pralidoxima. Oito serviços contavam com estoque adequado de N-acetilcisteína, porém em apresentações pouco apropriadas para uso como antídotos (ex: solução injetável 3 mg/mL para uso IV; envelopes de 100 mg, 200 mg ou 600 mg para uso VO ou por tubagem nasogástrica). Apenas sete apresentações estavam estocadas em todas as unidades avaliadas (atropina, bicarbonato de sódio a 8,4%, diazepam, fitomenadiona, flumazenil, glicose a 50% e gluconato de cálcio a 10%), seguidas de 13/14 unidades onde também havia estoque de carvão ativado e naloxona. Apenas uma unidade de emergência, pública e de referência regional no tratamento de intoxicações, contava com um estoque próximo ao delineado, com 25 antídotos e 27 apresentações farmacêuticas, porém sem estoque de anticorpos antidigoxina, fisostigmina, fomepizole, hidroxicobalamina, glucagon e pralidoxima. Conclusões: O estoque de antídotos nos serviços de emergência na cidade de Campinas é insuficiente e mal dimensionado, colocando em risco o tratamento de pacientes intoxicados / Abstract: Introduction: The lack of adequate and prompt availability of antidotes is a worldwide problem, with potentially disastrous consequences. Objective: To evaluate the availability of antidotes used in the treatment of poisonings in public and private emergency departments in the municipality of Campinas. Methods: A structured questionnaire was sent to the pharmacy directors of the public and private emergency departments from the Campinas municipality. The availability, amount in stock, stocking place, and access time in the emergency room (immediately or in first hour) to 31 antidotes in 33 pharmaceutical preparations was investigated, considering the stock of at least one full antidote treatment per service per an adult with an estimated weight of 70 kg. . The selection of antidotes was based on stock recommendations contained in international guidelines published by the end of 2009. Antivenoms were not included in the analysis. Results: Questionnaires were completed by 14 of 17 emergency departments operating at the time, 7 public and 7 private. No emergency department had all the 31 selected antidotes, and none of them had antidigoxin antibodies, physostigmine, fomepizole, hydroxocobalamin, or pralidoxime. Eight units had adequate stock of N-acetylcysteine, but in inappropriate presentations for use as antidotes (injectable solution 3 mg / mL for IV use; 100 mg, 200 mg or 600 mg envelopes for use by oral or nasogastric tube). Only seven presentations were stocked in all evaluated units (atropine, sodium bicarbonate 8.4%, diazepam, phytonadione, flumazenil, glucose 50% and calcium gluconate 10%), followed by 13/14 units where there was stock of activated charcoal and naloxone. Only one referral public department emergency in the treatment of poisonings had stocks close to the one outlined with 25 antidotes and 27 pharmaceutical forms, but without antidigoxin antibodies, physostigmine, fomepizole, hydroxocobalamin, glucagon and pralidoxime in stock. Conclusions: The stock of antidotes in emergency departments in the municipality of Campinas is inadequate and poorly scaled, jeopardizing the treatment of poisoned patients / Mestrado / Saude da Criança e do Adolescente / Mestra em Ciências
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SVERIGES BRISTANDE KRISBEREDSKAP – VARFÖR NEDMONTERADES TOTALFÖRSVARET? : Den rådande coronapandemin har lamslagit världen. Sveriges förmåga att hantera viruset har ifrågasatts och brister i beredskapen har återigen uppdagats. Varför nedrustades totalförsvaret?Larsson, Markus January 2020 (has links)
Den pågående coronapandemin har lamslagit stora delar av världen och brister i den svenska krisberedskapen har därmed uppdagats. Uppsatsens syfte är att förklara varför det svenska totalförsvaret nedrustades. För att kunna ge svar på forskningsfrågan kommer fem försvarsbeslut – försvarsbeslutet 1992, försvarsbeslutet 1996, försvarsbeslutet 2000, försvarsbeslutet 2004 och försvarsbeslutet 2009 – att analyseras. Besluten studeras utifrån en kvalitativ innehållsanalys, där Rational Actor Model används. Innehållsanalysen kompletteras med en kvalitativ forskningsintervju med den tidigare svenske försvarsministern Anders Björck. De teoretiska utgångspunkterna som studien följer är säkerhetisering, risker och hot. Bakgrundskapitlet behandlar den svenska beredskapen i nutid och det svenska försvarets historia. Tidigare forskning om beredskap och försvar internationellt lyfts fram tillsammans med hur delar av den svenska beredskapen har påverkats under de senaste 30 åren. Det rådande säkerhetsläget efter kalla kriget bidrog till nedskärningar i försvarsorganisationen, avskaffandet av ett invasionsförsvar och skapandet av ett insatsförsvar. Insatsförsvaret skulle ha hög operativ förmåga, såväl nationellt som internationellt och krävde därför förband av hög kvalitet, varpå värnplikten avskaffades. Beredskapslager ansågs inte vara lika behövande under det nya säkerhetsläget och det fördjupade samarbetet med den Europiska unionen skapade en naiv trygghet i att försörjningsberedskapen skulle kunna säkras genom medlemskapet. Arbetets slutsats till varför totalförsvaret nedrustades var det förändrade säkerhetsläget och en tilltagande tro på stöd från EU vid hanteringen av krissituationer i kombination med bristande historiekunskaper. / The ongoing coronavirus pandemic has paralyzed large parts of the world and shortcomings in the Swedish crisis preparedness have thus been discovered. The purpose of the thesis is to explain why the Swedish total defense was disarmed. In order to answer the research question, five defense decisions – the defense decision in 1992, the defense decision in 1996, the defense decision in 2000, the defense decision in 2004 and the defense decision in 2009 – will be analyzed. The decisions are studied based on a qualitative content analysis, using the Rational Actor Model. The content analysis is supplemented by a qualitative research interview with the former Swedish Defense Minister Anders Björck. The theoretical starting points that the study follows are security, risks, and threats. The background chapter deals with the Swedish preparedness of today and the history of the Swedish defense. Previous research on preparedness and defense internationally has been highlighted as well as how parts of Swedish preparedness have been affected over the past 30 years. The prevailing security situation after the Cold War contributed to cuts in the defense organization, the abolition of an invasion defense and the creation of an intervention defense. The intervention defense would have high operational capability, both nationally and internationally and therefore required high-quality associations and the military duty was abolished. Emergency preparedness stocks were not considered to be as needed during the new security situation, and the deeper cooperation with the European Union created a naive security that security of supply could be secured through the membership. The work's conclusion as to why the total defense was disarmed was the changed security situation and a growing belief in support from the EU in dealing with crisis situations, in combination with lack of historical knowledge.
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Stanovení potřeby provozního kapitálu z hlediska řízení činností zakázky / Determination of Working Capital Need for Process Management of Engagement ActivitiesHejlová, Věra January 2019 (has links)
This master thesis in theoretical part focuses on the system of process management and approaches to the need of working capital in connection with the company stock. It contains an analysis of the current commission process of the selected company in terms of factual and consequently also financial resources. It suggests the process of activities over time and the amount of stocks needed to them, to obtain the necessary amount and time of financial resources so that the company does not end in failure.
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IMPLEMENTING A TACTICAL TELEMETRY STYSTEM FOR MULTIPLE LAUNCH ROCKET SYSTEM (MLRS) STOCKPILE RELIABILITY TESTINGCox, Corry 10 1900 (has links)
International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / The Precision Fires Rocket and Missile Systems (PFRMS) Program Office continually undertakes
Stockpile Reliability Testing (SRP) to ensure the validity of the accumulated weapons and increase
the she lf life of these weapon systems. MLRS is a legacy weapon system that has been undergoing
SRP testing for over 20 years. The PFRMS Program Office has a need for a miniature Tactical
Telemetry System that will monitor the fuze performance of the MLRS Rocket during SRP testing.
This paper will address a technical approach of how a small Tactical Telemetry System could be
built to meet this requirement. The Tactical Telemetry system proposed in this paper will monitor
fuze functions, operate across the wide environmental spectrum of the SRP tests, and physically fit
in the nose area without altering the overall tactical rocket appearance or operation.
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Sequenciamento e programação de lavra com alocação de equipamentos de carga. / Scheduling of mining with allocation of loading equipments.Andrade, Arthur Quintão de 08 April 2014 (has links)
Este trabalho tem seu foco no problema de sequenciamento e programação da lavra em mina a céu aberto, com alocação de equipamentos de carregamento. Neste estudo considera-se a existência de uma frota heterogênea de equipamentos de carga e dois tipos de material lavráveis, sendo minério ou estéril. Para a lavra de minério são considerados requisitos de qualidade a serem atingidos pela mistura de minério, um britador, uma capacidade de operação atribuída à usina de beneficiamento e uma pilha de estoque objetivando abastecer a usina quando faltar minério nas frentes de lavra, denominada pilha de ROM. Em uma mina o carregamento pode ser gerido por um plano de lavra que descreve a movimentação e a produção horária de cada equipamento de carga ao longo do tempo. Neste contexto, apresenta-se um modelo matemático apoiado por um algoritmo responsável por mover o horizonte de tempo a cada execução do modelo com intuito de gerar ordens de lavra resolvidas com otimalidade. Juntas, essas ordens descreverão o plano de lavra dos equipamentos de carga. Os experimentos computacionais, realizados utilizando dados de uma jazida de cobre, mostram a efetividade da proposta considerando um horizonte de médio prazo. / This paper focuses on the mining scheduling problem in open pit, considering the allocation of loading equipment. This study considers the existence of a heterogeneous fleet loading equipment and two types of mineable material, namely ore or waste. For the mining of ore are considered quality requirements to be met by the ore blending, a crusher, the capacity of operation of the processing plant and a stockpile which feed the plant when there is lack of ore in mining fronts, called ROM stockpile. In a mine, loading can be managed by a mining plan that describes the movement and the schedule of each load equipment over time. In this context, we present a mathematical model supported by an algorithm that is responsible for moving the time horizon for each model run, with the goal of generating mining orders till resolved to optimality. Together, these orders describe the mining plan of the loading equipment. The computational experiments, conducted using data from a copper deposit, show the effectiveness of the proposal considering a medium-term horizon.
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