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1
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PATRICK TEIXEIRA OLIVEIRA
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Haulage productivity increase using telemetry in a phosphate mine in the Alto Paranaíba Region -MG
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Líder : MARCELIO PRADO FONTES
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MIEMBROS DE LA BANCA :
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LUCIANO NUNES CAPPONI
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MARCELIO PRADO FONTES
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MICHEL MELO OLIVEIRA
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WALTER SCHMIDT FELSCH JUNIOR
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Data: 10-feb-2022
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Resumen Espectáculo
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The competitiveness that companies face in the market becomes more and more intense, so it is of great importance that processes are carried out efficiently, minimizing losses. In mining, the exploration phase allows for cost reduction with good management of ore and waste loading and transport operations for the subsequent stages of the production process. The transport of these materials is mostly done by trucks, whose productivity is directly influenced by the average speed. This work defined, created tools and dashboards for managing average speed. Thus, enabling better management of team performance, mapping and field work to improve access conditions. The results of the work showed an increase in productivity of 13% for the Caterpillar fleet and 10.8% for the Komatsu fleet, leading to savings of R$3.078 million in operating costs. Improvements were also identified in the safety and ergonomics of the roads and standardized direction of access maintenance resources.
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2
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GABRIELA BRENDA DE LIMA RIBEIRO
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High-performance concrete (HPC) using phosphate ore magnetic tailings
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Líder : MARCELA MAIRA NASCIMENTO DE SOUZA SOARES
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MIEMBROS DE LA BANCA :
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MARCELA MAIRA NASCIMENTO DE SOUZA SOARES
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AUGUSTO CESAR DA SILVA BEZERRA
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ALEXANDER MARTIN SILVEIRA GIMENEZ
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FLAVIA SPITALE JACQUES POGGIALI
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DAYANA CRISTINA SILVA GARCIA
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Data: 27-jun-2022
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Resumen Espectáculo
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The increasing amount of tailings generated in mining activities has raised the interest of several researchers in providing an appropriate destination for them. At the same time, the pursuit of sustainable materials provides motivation for using magnetic tailings as a fine aggregate in concrete. This study aims to develop a high-performance concrete (HPC) with partial replacement of the fine aggregate by magnetic tailings derived from the phosphate rock beneficiation process in Araxá in the Alto Paranaíba Mesoregion of Minas Gerais. The purpose is to improve the pore structure of concrete by optimizing the packing of granular materials and incorporating mineral addition, as well as adjusting the workability using chemical additive. After determining the concrete mix, cylindrical specimens will be molded (10 cm × 20 cm), then they will remain in wet curing for 28 days. Following that, the properties of the concrete produced in the hardened state will be evaluated through the tests: compressive strength, modulus of elasticity, water absorption, specific weight and durability when exposed to sulfuric acid attack. The results will be compared with the reference concrete to evaluate the feasibility of the proposed replacement. It is expected to produce a concrete with a slump of approximately 150 mm, dense matrix, compressive strength greater than 60 MPa and that presents good durability.
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3
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ANDRÉ RICARDO CALCIOLARI
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EVALUATION OF BIOCHAR PREPARATION FROM SILVER COFFEE SKIN PYROLYSIS AND ITS VIABILITY IN THE REMOVAL OF Pb2+ IONS FROM AQUEOUS SOLUTION
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Líder : MARIO GUIMARAES JUNIOR
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MIEMBROS DE LA BANCA :
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MARIO GUIMARAES JUNIOR
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MICHELLY DOS SANTOS OLIVEIRA
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JOÃO RODRIGO COIMBRA NOBRE
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CORDÉLIA ALVES RIOS
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Data: 27-jun-2022
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Resumen Espectáculo
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The mineral sector stands out as one of the industrial activities that most impact the environment. In this sense, it has contributed to the generation of a large of tailings and solid wastes that can contain a wide range of toxic metals. Added to this is the generation of waste of another nature from agricultural activities that also impact the environment when discarded without any treatment. From this perspective, biochar has been investigated as a promising alternative to improve water and soil quality. Its adsorptive properties can be enhanced by optimizing of its production conditions and/or by physical or chemical activation. However, although activation has several advantages, it almost always results in high cost and secondary waste generation. This work aimed to evaluate the potential of coffee silverskin biochar (BC) in the removal of the Pb2+ ions from in aqueous solution. The BC was prepared in a low-oxygen muffle furnace at five temperature levels (338 °C, 400 °C, 550 °C, 700 °C, and 768 °C) and residence times (95, 120, 180, 240, and 265 min) with a heating rate of 10 °C/min. The experimental design is based on the central composite design 22, with 5 repetitions in the center. The experimental design was applied to investigate the effects of temperature and residence time variables on methylene blue (MB) adsorption capacity and BC yield. Studies of kinetics and equilibrium of adsorption of MB were also carried out to verify the adsorbent potential of the material. The BC with the best adsorption performance was selected and evaluated egarding its ability to remove Pb2+ ions from aqueous solutions. This BC was subjected to additional characterizations regarding its specific surface area (N2 adsorption), surface functional groups (FTIR), elemental analysis (CHNS-O), surface charge (Zero point charge - ZPC), thermal stability (TG/DTG), chemical structure and crystallinity (Raman Spectroscopy/XRD). The results obtained from the response surface methodology (RSM) revealed that the pyrolysis temperature exerted significant effects on the adsorption capacity and yield of BC. The combination of parameters that came closest to the optimal conditions determined by the RSM was regarding the BC prepared at 400 °C and 120 min (BC1). The kinetic and equilibrium data were better fitted by the Elovich (R2(aj.) = 0.998; χ2 = 5.495) and Langmuir (R2(aj.) = 0.952; 2χ = 106.714) models, respectively, suggesting that chemisorption was the dominant mechanism and that the adsorption occurred in monolayer. The theoretical maximum adsorption capacity (Qmax), for BC1, of 160.08 mg/g and the value of the separation factor (RL), between 0.58 and 0.03; indicate that the adsorption of MB by BC1 was favorable. The amount of lead remaining was quantified by the microwave induced plasma optical emission spectrometry (MIP-OES) technique. The BC1 showed an efficiency of 93.0% in the removal of Pb2+ ions from the aforementioned solution. Additional tests showed that the BC7 sample, pyrolyzed at 550 °C for 95 min, removed up to 96.6% of Pb2+ ions from the same solution, showing an excellent fit and reliability of the results. Therefore, PPC BCs can be considered promising adsorbents for the decontamination of lead ions present in an aqueous solution and can be a sustainable and more affordable alternative when compared to activated carbon.
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4
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Laura Borges Costa
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Mortar feasibility study with phyllite addition
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Líder : ALEXANDER MARTIN SILVEIRA GIMENEZ
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MIEMBROS DE LA BANCA :
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ALEXANDER MARTIN SILVEIRA GIMENEZ
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DELMA PEREIRA CAIXETA
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FABIO DE SAO JOSE
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MARCELA MAIRA NASCIMENTO DE SOUZA SOARES
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Data: 29-jun-2022
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Mining has a huge influence on the world’s economy, being responsible for the generation of several direct and indirect jobs. However, mining collides with a recurrent and inherent process in the industry: waste generation. Environmental sustainability actions have been adopted in different production line aiming to reduce the impacts involved on the generation and storage of that waste materials. Therefore, the goal of this project is to apply phyllite, an abundant rock in Brazil, and often considered as a waste of mining, in mortars as a substitute for binder (lime) and fine aggregate, without changing the properties of the mortar due to the presence of the phyllite, and aiming inserting in the market a new product with good technical performance and economic viability. For this, laboratory tests were carried out following national standards, totaling a standard mix and five replacements in traditionally dosed mortar in the proportion of 1:1:6 in volume of cement, binder and sand, in which 50% of the fine aggregate was replaced by different granulometric ranges of phyllite and 37.5% and 75% of the quantities of phyllite inserted as a binder substitute. Cylindrical specimens of 5x10 cm and squares of 5x5x5 cm were molded in order to perform uniaxial compressive strength, permeability, hardened state density tests, as well as water retention tests, fresh density tests. Furthermore, the mortar was applied to a roughened wall in order to analyze its performance and perform the permeability test. Through the tests’ preformation, is possible to conclude that the presence of phyllite on the mortar improves the analyzed properties such as uniaxial compressive strength, permeability, hardened state density tests, water retention tests, fresh density tests when compared with the standard mortar, especially the substitutions C1A and C1A2.
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5
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JOAO VICTOR DA SILVA ALVES
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EVALUATION OF MAGNAFLOC AND SODIUM ALGINATE REAGENTS FOR TREATMENT OF MINERAL EFFLUENT FROM FERTILIZER COMPANIES USING DISSOLVED AIR FLOTATION
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Líder : NATAL JUNIO PIRES
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MIEMBROS DE LA BANCA :
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NATAL JUNIO PIRES
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ALEXANDER MARTIN SILVEIRA GIMENEZ
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MICHELLY DOS SANTOS OLIVEIRA
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FERNANDO BRANDAO RODRIGUES DA SILVA
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LEANDRO HENRIQUE SANTOS
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Data: 30-jun-2022
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Water is a strategic resource for mining, especialy in the processing of ores. Thus, the best use of this resource, including its reuse, is essential given its scarcity and increasingly stringent environmental restrictions. However, the reuse of water, especialy in flotation, can reduce the efficiency of the process, due to the presence of the various ions dissolved in it. For phosphate ore flotation, magnesium, fluoride, phosphate and calcium ions frequently occur in reuse water and can impact flotation results. In this sense, this work aimed to obtain a better quality water through coagulation, flocculation and dissolved air flotation (FAD), in order to enable its reuse and thus be able to reuse it in the apatite flotation. To develop this work, samples of reused water (tailings dam), new water and ore samples were colected from a fertilizer company located in Alto Paranaíba. A factorial design was carried out to evaluate the treatment of reuse water using the reagents Magnafloc and Sodium Alginate. With this, a better quality treated water was obtained, which could be used in the apatite flotation. Apatite flotation tests were also carried out using untreated reuse water and fresh water so that it is possible to compare the flotation efficiency. With this work, it was achieved that the treatment of reuse water via coagulation, flocculation and FAD is a technical solution for the treatment of this effluent, whether for reuse in apatite flotation or for return to springs.
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6
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JOÃO ANTÔNIO TEIXEIRA SOARES
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SAFETY OF DAMS BASED ON STATISTICAL OPERATIONAL CONTROLS
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Líder : THIAGO BOMJARDIM PORTO
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MIEMBROS DE LA BANCA :
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THIAGO BOMJARDIM PORTO
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NATAL JUNIO PIRES
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RONDERSON QUEIROZ HILÁRIO
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MARCOS ANTÔNIO LEMOS JÚNIOR
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JOÃO FRANCISCO ALVES SILVEIRA
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Data: 22-jul-2022
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The operation phase of dams can extend for decades and, therefore, monitoring and inspection activities are essential. Auscultation of dams aims the safety conditions assessment and checking of design assumptions. This system generates a huge database that needs to be processed to obtain information about the behavior of the structure. The representative database should be used to statistical analyses that enables the identification of standards about the soil behavior, seasonality and, mainly, the rapid identification of behavior changing of the structure based on statistical operational controls. To understand the complex performance and behavior of dams, the monitoring should integrate the monitoring technologies, automated instrumentation, friendly and intuitive platform to results visualization and the implantation of deterministic and statistical operational control. Therefore, was observed the potential of development of a statistical operational control using the Multiple Linear Regression (MLR), that is the one of most techniques used to model the linear correlation between a dependent variable and one, or more, independent variables. The utilization of MLR to identification of water table or piezometric line (dependent variable) in relation of independent variables: reservoir water level, rainfall and v-notch data. The database used in the study consist of 20 water level indicators, 5 piezometers, 1 reservoir level indicator and 1 v-notch wier according to a period between 2017 and 2021. After the development phase, was possible to characterize scenarios of operation like the seasonality and even anomalous scenarios like rainwater infiltration inside the instrument. Among the 25 instruments, the MLR proved to be satisfactory to 16 of them, with a prediction potential up to 97%. After the conclusion of the research, was certified that Multiple Linear Regression applied to statistical control levels of dam’s safety complies with the best practices of monitoring of dams.
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7
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AMANDA APARECIDA CARNEIRO
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Líder : MARIO GUIMARAES JUNIOR
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MIEMBROS DE LA BANCA :
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ANTÔNIO EDUARDO CLARK PERES
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LÍLIAN LIS DE ANDRADE CANTUÁRIO COSTA
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HENRIQUE GONÇALVES TEIXEIRA
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MARIO GUIMARAES JUNIOR
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MICHELLY DOS SANTOS OLIVEIRA
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Data: 30-sep-2022
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8
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TIAGO ALVES
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METHODOLOGY FOR ANALYSIS OF COSTS FOR SIZING LOADING AND TRANSPORTATION FLEETS IN AN OPEN CART MINE
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Líder : HENRIQUE JOSE AVELAR
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MIEMBROS DE LA BANCA :
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HENRIQUE JOSE AVELAR
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MICHEL MELO OLIVEIRA
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WALTER SCHMIDT FELSCH JUNIOR
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Data: 20-oct-2022
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The constant availability of new technologies and the advancement of industry 4.0 are transforming the mining scenario around the world. Every year new tools and functionalities are made available, the size of the equipment is maximized and techniques for productivity gains are implemented in the operations. In a mine operation, loading and transport activities are responsible for a large part of the total expenses and the dimensioning of the resources to be applied in them must be carried out with absolute criteria and with analyzes that make it possible to find the best scenario. It is in this context that the correct dimensioning of equipment in a mine operation becomes increasingly important, in order to obtain the best cost-benefit optimization, maximizing financial gains. This work presents techniques for analyzing and sizing loading and transport equipment in open pit mine operations, as well as demonstrating how the search for a combination of these equipment is essential for an efficient operation. In addition, the work presents and demonstrates how the development of a tool that correlates and groups the main resources and techniques necessary and available for the elaboration and analysis of sizing, can bring a more robust and consistent result for decision making.
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9
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MARIA EUGÊNIA FERREIRA CAMPOS
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DEFORMATION ASSOCIATED WITH THE ALKALINE-CARBONATITIC INTRUSION OF TAPIRA, MINAS GERAIS
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Líder : HILDOR JOSE SEER
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MIEMBROS DE LA BANCA :
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MARIA EUGÊNIA SILVA DE SOUZA
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ALLAN ERLIKHMAN MEDEIROS SANTOS
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CARLOS HUMBERTO SILVA
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HILDOR JOSE SEER
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Data: 27-oct-2022
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The Tapira Alkaline-Carbonatitic Complex is a domic intrusion, with an elliptical shape on the surface, approximately 6.5km in diameter and 35km² in area, resulting from the amalgamation of two ultrabasic magma intrusions, five of carbonatite and one of syenite, occurring embedded in quartzites and pre-Cambrian shales of the Canastra Group. Located 35km southwest of Araxá, the Tapira complex has great economic relevance as it houses the largest phosphate rock mining in Brazil, also having residual deposits with no current economic use of niobium, titanium and rare earths, which are located in the mantle of weathering . This complex is the result of a regional magmatic event that gave rise to a set of intrusive circular structures aligned for more than 1000km in the NW-SE direction and pyroclastic flows of kamafugitic affiliation, known as the Alto Paranaíba Igneous Province (APIP). The structural features recognized in the surroundings of the complex show that the spatial attitude of the main foliation of the enclosing rocks, of Neoproterozoic origin, was modified by the intrusion process, where low angle dips to steep dips are observed, with ring patterns around the dome. The detailed structural mapping will allow to know the deformational effects caused by the process of igneous rise of the domic intrusion originating in the complex. Understanding the structural framework of the region's lithologies may be a subsidy for future studies on the hydrogeological behavior of fissured aquifers in the region, as well as for mine planning, construction of dams and other structures supported on the rock mass, especially those built by fertilizer mining company, currently MOSAIC.
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10
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MARIA VIRGÍNIA DA CUNHA
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EVALUATION OF DISPERSION IN THE SLIDING AND PHOSPHATE ORE FLOTATION
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Líder : MICHELLY DOS SANTOS OLIVEIRA
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MIEMBROS DE LA BANCA :
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FABIO DE SAO JOSE
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LUCIANO FERNANDES DE MAGALHAES
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MARIO GUIMARAES JUNIOR
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MICHELLY DOS SANTOS OLIVEIRA
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Data: 28-oct-2022
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Deslaming is one of the stages of the processing of phosphatic ore, responsible for the removal of fines and slats. It is known that the presence of fines can cause numerous problems in the flotation stage, such as excessive expenditure of reagents and coating of coarse particles by slime coating. Within this line of reasoning, the present work is justified by the benefits brought by the elimination of very fine particles, which favors the increase of selectivity and the recovery of P2O5. The reduction in the amount of reagents followed by increased efficiency of the deslaming stage are also auspicious hypotheses. Furthermore, the purpose of the project is to investigate the influence of dispersion on deslamation and flotation of phosphotic ore, in addition to articulating the comparison of dispersants and pH values, using for this outcome the calculation of the degree of dispersion, global metallurgical recovery, the selectivity ratio and the analysis of content in the deslamation and flotation operation. In this sense, it is expected with this research, the optimization of deslamation and also flotation, seeking better results, through dispersion techniques. To achieve these goals, flotation tests; deslaming combined with flotation; dispersion combined with deslamion and flotation; and dispersion combined with flotation, were produced and verified. For this, a sample of phosphatic ore from a company located in the Alto Paranaíba region, in the state of Minas Gerais, was used. The dispersion tests were performed by means of a dispersion tube and optimized with the aid of the Minitab software. Flotation and deslamation assays were performed in mechanical cells. The use of dispersants proved to be efficient for deslaming because it decreased the value of metallurgical loss. However, dispersants previously added to flotation contributed to increase metallurgical recovery, but only one assay had an increase in P2O5 content. The sodium hexametaphosphate reagent at the dosage of 3000 g/t provided the highest degree of dispersion, but in the bench flotation presented the lowest values of metallurgical recovery and P2O5 content. The experiment using sodium silicate, with deslamion and dosage of 3000 g/t, was the best condition for both deslamation and flotation. Finally, when comcing the flotation assay and flotation assay with deslamation (both without adding dispersants), it is observed that despite the decrease in metallurgical recovery, there is an increase in P2O5 content and selectivity ratios. These increases may justify the use of deslamation preceding flotation.
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11
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SARA NUZA OLIVEIRA DOS REIS GONÇALVES
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PHOTOCATALYTIC PERFORMANCE OF ALCALI MATERIAL ACTIVATED ON THE BASE OF RED MUD AND BLAST FURNACE SLAG
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Líder : AUGUSTO CESAR DA SILVA BEZERRA
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MIEMBROS DE LA BANCA :
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AUGUSTO CESAR DA SILVA BEZERRA
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DOMINGOS SAVIO DE RESENDE
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MARCELA MAIRA NASCIMENTO DE SOUZA SOARES
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GUILHERME JORGE BRIGOLINI SILVA
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Data: 31-oct-2022
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One of the main concerns of the mining industry is the large amount of waste generated in mineral extraction and processing. In addition to causing impacts on the environment, these wastes occupy large areas and can cause problems in their disposal. Many studies have been and are being performed in order to reuse these environmental passives, aiming to reduce environmental damage. Based on this, this work seeks to produce alternative materials to Portland cement through the alkali activation process of industrial waste. On a second step, these alkali-activated materials (AAMs) will be investigated in relation to their degrading potential of solutions of methylene blue dye (MB) from synthetic effluents. The alkali activated materials will be produced essentially from red mud (RM) and blast furnace slag (BFS), which will be ground to pass 200 mesh sieves. These precursors will be characterized through laser granulometry, X-ray fluorescence spectrometry (XRF), X-ray diffraction (XRD), loss-on-ignition (LOI), thermogravimetry (TGA), adsorption and desorption of nitrogen gas (BET) and scanning electron microscopy (SEM). The literature review supported the AAMs definitions of main parameters of composition, dosage and production methodologies. The alkali-activation effectiveness will be determined through compression resistance and water absorption tests and microstructural analysis of the AAMs formed. Then, the mix in which it was possible to obtain better mechanical strength and good decontaminating potential will be evaluated.
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12
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INGRID GUIMARÃES SILVEIRA E SILVA
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Hydro-Geotechnical Modelling of a Tailings Dam raised centerline
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Líder : DENISE DE CARVALHO URASHIMA
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MIEMBROS DE LA BANCA :
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DENISE DE CARVALHO URASHIMA
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EDUARDO SOUZA CÂNDIDO
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LUCAS DELEON FERREIRA
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Data: 31-oct-2022
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In the ore beneficiation process tailings that can be discarded in the form of pulp or mud, in structures such as dams or dykes are generated. In the event of a break, those tailings can cause high environmental, social and economic damage. Moreover, the process of monitoring and safety of tailings dams presents some hydro-geotechnical complexity. In this context, this research presents a stability study, through numerical modeling of a phosphate tailings dam raised by the centerline method. The modelling framework is based on the knowledge of the groundwater flow and seepage networks, which are applied to verify the safety factor of the structure in two different scenarios: the first considers a high water level (NA) and flooding in the downstream region of the dam and the second considers the execution of works that reinforce and drawdown of the reservoir water level. It is noteworthy that the second scenario complies with premises established by the Agência Nacional de Mineração (ANM) for the stability condition . Thus, this study is based on field and laboratory geological-geotechnicals investigations that were used to support the necessary inputs in the numerical modeling, carried out by the SLIDE software from ROCSCIENCE. From the database analysis, two geological-geotechnical sections were defined, called B-B' and E-E', as being the most representative of the dam under study. To represent the boundary conditions of the model, the average permeabilities of each constituent material of these sections were determined, as well as the elevations of piezometers and water level meters. For the stability analysis, preterits strength parameters are being used, which enabled the analysis of global and partial safety factors in drained and undrained conditions. A preliminary result of the geological-geotechnical section E-E', presents for the first scenario global safety factors equal to 2.06 and 1.32 for the drained and undrained condition, respectively. Partial safety factors equal to 1.96 and 1.32 for the drained and undrained condition, respectively, were found as well. Therefore, the undrained condition, for the first scenario of section E-E', did not meet the recommended in ABNT NBR 13.028:2017, which defines the safety factor greater than or equal to 1.50 for operation with seepage network in normal condition. The next stages of the research aim to compare the results of the first and second scenarios, from both geological-geotechnical sections B-B' and E-E', in order to numerically evaluate the efficiency of the corrective maintenance works performed.
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13
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VITOR AFFONSO LOPES SILVEIRA
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Waste from the Sanitary Ceramic industry as Supplementary Cementium Material
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Líder : DOMINGOS SAVIO DE RESENDE
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MIEMBROS DE LA BANCA :
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ALEXANDER MARTIN SILVEIRA GIMENEZ
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DOMINGOS SAVIO DE RESENDE
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MARCELA MAIRA NASCIMENTO DE SOUZA SOARES
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AUGUSTO CESAR DA SILVA BEZERRA
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ANTONIO MARIA CLARET GOUVEIA
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Data: 31-oct-2022
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The manufacturing process of sanitary ceramics leads to the generation of industrial waste with different characteristics, obtained according to the processing steps in which they are generated and the products manufactured. The chemical composition of these materials are similar of their raw material, and their physical properties can be easily modified in order to reuse them. Thus, several works have been developed to value materials like this. It is believed that they can be used as a supplementary raw material in the production of civil construction objects, either through their application as aggregates or even as a partial replacement for Portland cement. To contribute to the carbon footprint, as well as the preservation of mineral resources, the cement industry has used supplementary cementitious materials (SCM) as a partial replacement of clinker in Portland cement. In this sense, the present work evaluated the reuse potential of solid waste accumulated in a settling pond of an industry located in the Minas Gerais triangle. For this, the collected sample was characterized by granulometric analysis, X-ray diffraction, X-ray fluorescence, microscopy, and loss on ignition. To evaluate the residue as SCM, tests of heat of hydration, electrical conductivity in calcium hydroxide solution and determination of the performance index with Portland cement were carried out. Concrete mortars were produced with partial replacement (12.5% and 25%) of a cement with reduced additions by the residue. These mortars were evaluated by means of compressive strength at seven and 28 days, specific mass, voids ratio, water absorption and performance against acid attack. The chemical composition by XRF indicated the oxides SiO2, CaO and Al2O3 and the XRD analysis points to the presence of quartz, kaolinite and bassanite as predominant minerals. The application of the residue reduced the heat of hydration and the porosity of the mortar, leading to an increase in its durability. Although the electrical conductivity results point to non-pozzolanicity, the compressive strength did not show significant changes, which suggests that the residue can be used in pozzolanic cement compositions (CP IV).
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14
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MARINA MARTINS
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EFFECT OF FLOCCULANTS IN THE THICKENING AND RHEOLOGY OF IRON ORE TAILING SLURRYS
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Líder : MICHELLY DOS SANTOS OLIVEIRA
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MIEMBROS DE LA BANCA :
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MICHELLY DOS SANTOS OLIVEIRA
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NATAL JUNIO PIRES
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FRANCISCO GREGIANIN TESTA
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SILVIA CRISTINA ALVES FRANÇA
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Data: 31-oct-2022
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The storage of tailings in the form of diluted pulp has been a critical issue for a mineral, as tailings dams are difficult and costly to monitor. In view of this, the dewatering of the tailings becomes an alternative so that the dams can contain smaller volumes of water. Thickening is the main process for dewatering the tailings, and the use of flocculants at this stage is essential so that the fine particles can settle more efficiently. This work aimed to evaluate the influence of different flocculants on the dewatering and rheology of an iron ore tailings. For this, sedimentation tests were carried out in proof in order to obtain the sedimentation velocity, turbidity of the clarified and % of solids in the underflow. To evaluate the influence of the reagents on the rheology of the material, rheological slump tests were carried out in a rotational rheometer. The accumulated reagents were polyacrylamides from the Magnafloc, Alclar and Rheomax lines from BASF and also a residual potato starch. The results showed that the reagents positively interfered in the sedimentation and rheology of the tailings. Among the improved synthetic reagents, Rheo 1050 at a dosage of 30g/t was the one that clarified the best results with a maximum sedimentation velocity of 0.76 cm/s, a minimum turbidity of 60.5N and 53.75% solids. no underflow. The maximum yield stress of the tailings slurry, 141 Pa, was also achieved for this same reagent and in the mass concentration of solids of 75%, classifying the thickened tailings as high density waste.
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15
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FRANCISCO DE CASTRO VALENTE NETO
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MAGNETIC WASTE INCORPORATION INTO ACTIVATED ALCALI MATERIALS
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Líder : DOMINGOS SAVIO DE RESENDE
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MIEMBROS DE LA BANCA :
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DOMINGOS SAVIO DE RESENDE
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MARCELA MAIRA NASCIMENTO DE SOUZA SOARES
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ALEXANDER MARTIN SILVEIRA GIMENEZ
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AUGUSTO CESAR DA SILVA BEZERRA
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ANTONIO MARIA CLARET GOUVEIA
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Data: 20-dic-2022
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Resumen Espectáculo
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It is common knowledge that the cement industry is one of the largest producers of CO2 on the planet, starting from the burning of fuel (coal, fuel oil or gas) and the transformation of calcium carbonate into calcium oxide in the formulation of clinker, Portland cement. common. In this way, several studies are carried out to investigate the reduction and/or replacement of this cement, one of them is the alkali activation process of specific materials for the formation of a compound with agglomerating properties. In addition, there is another environmental problem resulting from the tailings generated by mining, which are usually deposited in dams. One of these wastes is magnetic waste, which basically consists of the mineral magnetite, and which, to date, no technical and economic way has been found for its use. Therefore, this work aims to incorporate the magnetic waste in alkali-activated materials in order to study the physical and mechanical behavior of these compounds. For this purpose, magnetic tailings were used, originating from the processing of phosphate ore from a mine in Goiás, and blast furnace slag from the production of pig iron was used as a precursor. The magnetic waste, as it was received, was dried in an oven and sieved. The blast furnace slag was received already dry and sieved. All these materials were characterized by X-Ray Diffraction (XRD), X-Ray Fluorescence (FRX). The blast furnace slag was activated with sodium hydroxide PA. Specimens measuring 25 mm in diameter and 50 mm in height were made with activated alkali slag only (REF), with activated alkali slag and sand (EA) and with activated alkali slag and magnetic waste (ERM). The curing period was 7 and 28 days, from which tests were carried out on compressive strength, water absorption, and sulfuric acid attack. It was verified that the magnetic waste contributed positively to the studied mechanical properties. In this way, it is expected to contribute to a better understanding of the behavior of this type of composite.
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