http://repositorio.ufc.br/handle/riufc/58661 2026-07-27T19:22:26Z 2026-07-27T19:22:26Z Costa, Jesus Lucas Cavalcante http://repositorio.ufc.br/handle/riufc/87220 2026-07-22T19:45:21Z 2026-01-01T00:00:00Z

Título: Avaliação de plano de fogo para desmonte de rochas em uma mina de calcário baseada na previsão da fragmentação pelos métodos de Kuz-Ram e KCO Autor(es): Costa, Jesus Lucas Cavalcante Abstract: The blasting of rocks using explosives in limestone quarries dedicated to the cement industry holds strategic importance, as it ensures efficient fragmentation of rock masses and sustains the sector’s production chain. This technique enables the processing of large volumes of rock within a short time frame, ensuring optimization and productivity in the unit operations of loading, transportation, and comminution. However, when the blast design is inadequate, several negative consequences may occur, such as the formation of boulders, the presence of toes, and excessive flyrock—factors that compromise operational safety and increase production costs. In this context, it becomes essential to develop studies that allow understanding and controlling the parameters that directly influence the fragmentation of rock masses. This research aims to analyze the granulometric curves generated by the empirical Kuz-Ram and KCO methods in a quarry of the cement sector, comparing them with data processed in the WipFrag software from images of a rock blast. To achieve this goal, a methodology based on granulometric prediction through the mathematical fragmentation models Kuz-Ram and KCO will be employed. The choice of these two models is justified by the fact that Kuz-Ram, although widely used, presents limitations in describing finer particle sizes, whereas KCO, based on the Swebrec equation, proves more efficient in representing the complete granulometric behavior. Through their combined application, it was possible to perform a comparative study between theoretical granulometric curves and the actual curve obtained in the field, allowing the evaluation of model adherence to real conditions, identification of deviations, and assessment of the need for adjustments in the blast design to optimize fragmentation. As a result, it was found that the curve generated by the KCO method was closer to the curve produced by WipFrag than that generated by Kuz-Ram. Consequently, the application of the KCO method calculated a D80 = 56.23 cm, proving more representative compared to the institutional target (D80 = 60 cm), while the Kuz-Ram method predicted D80 = 52.42 cm. It was also observed that the granulometric curve generated by WipFrag did not identify the presence of boulders, highlighting the need to collect more representative images of the blasted pile. Finally, it is evident that parameters of the rock mass and the explosive must be considered for a more effective blast design, predicting different geometric parameter values for dissimilar rock masses. Tipo: TCC

2026-01-01T00:00:00Z Souza, Antonio Ítalo Rodrigues de http://repositorio.ufc.br/handle/riufc/84789 2026-02-13T15:57:29Z 2026-01-01T00:00:00Z

Título: Análise de custos da aplicação do sistema de iniciação não elétrico em uma pedreira dos Sertões de Crateús-CE Autor(es): Souza, Antonio Ítalo Rodrigues de Abstract: The rock breaking stage is fundamental in the mining process, as it directly influences operational efficiency, production costs, and the quality of fragmentation required in subsequent stages of mining. In this context, this study analyzes the technical and economic feasibility of applying the non-electric initiation system (NONEL) in a blasting plan developed for a gneiss quarry, considering that the costs of explosives and accessories represent a significant portion of blasting operations. The methodology adopted was based on a literature review, collection of geological and operational data from the quarry studied, and the development of new firing plans using the NONEL system, considering parameters such as distance, spacing, bench height, explosive charge distribution, and firing sequence. The results obtained and bibliographic studies indicate that the use of NONEL provides greater reliability in shock wave transmission, with a possible reduction in detonation failures, in addition to contributing to a decrease in the consumption of explosives and accessories. The main advantages of the system include greater operational safety, resistance to electrical interference, and the potential for reduced consumption of explosives. A disadvantage is the possibility of occasional failures associated with loss of contact in the charge column. Overall, the cost analysis showed a reduction in overall blasting costs from R$257,300.64 to R$105,285.08, or R$123,232.79, when two Nonel accessories were used per hole, showing that the NONEL system is a technically efficient and economically advantageous alternative, contributing to cost optimization and the reduction of operational risks in open-pit mining activities. Tipo: TCC

2026-01-01T00:00:00Z Silva, Joice Maria de Paiva http://repositorio.ufc.br/handle/riufc/84763 2026-02-12T17:07:11Z 2026-01-01T00:00:00Z

Título: Uso do método de enumeração completa para otimização da mistura de calcário para indústria cimenteira Autor(es): Silva, Joice Maria de Paiva Abstract: The mining sector has been undergoing significant transformations in the global economic landscape, marked by an increasingly competitive and technological environment. Companies in the sector have been directing efforts towards improving their production processes, aiming to increase operational efficiency and productivity while simultaneously seeking to reduce costs. In this context, there is a growing interest in the use of operational research tools to support decision-making. This area stands out for allowing the modeling and analysis of different qualitative and quantitative variables in diverse situations, providing a more precise evaluation in the planning of solutions. For mining companies, which frequently make decisions based on previous practical experiences, operational research represents an opportunity for a technical and structured approach. A practical example of its application is in the formation of ore piles generated by materials with different qualities in different mining fronts, a common challenge faced by these companies. In this sense, the present study aims to address the need to optimize the process, aiming to maximize the production of material that meets the grades required by quality control and to assist in the short-term planning of a limestone mine. To achieve this objective, an on-site survey was conducted to obtain the main parameters of the mining company's production process: equipment capacity, daily production of each tunnel, and the limits of quality control parameters (Lime Saturation Factor - CSF, Silica Modulus - MS, and Alumina Modulus - MA) for the different types of limestone. The Complete Enumeration method was applied to the modeling in conjunction with Excel software, an approach that enabled the generation of solutions that meet operational and quality constraints, in order to obtain viable solutions for the problem observed in cement production. The results demonstrated that the model was able to generate viable solutions for scenarios I, II, and III, meeting the established quality limits and the production required by the plant, proving its effectiveness in defining the ideal mixing proportions between the stockpiles. Tipo: TCC

2026-01-01T00:00:00Z Djassi, Djibril http://repositorio.ufc.br/handle/riufc/84723 2026-02-11T16:13:40Z 2026-01-01T00:00:00Z

Título: Avaliação da alterabilidade química de quartzitos ornamentais do Estado do Ceará Autor(es): Djassi, Djibril Abstract: This study aimed to carry out the petrographic characterization and the evaluation of the chemical alterability of two ornamental quartzites widely used in the state of Ceará: Perla Santana and Bianco Supreme. The research is framed within the context of the growing economic importance of the ornamental stone sector in Brazil, especially quartzites, which have been gaining prominence in the international market due to their high added and aesthetic value. Considering that the durability and aesthetic performance of these rocks are directly related to their resistance to chemical agents, this study seeks to understand how mineralogical, textural, and petrographic characteristics influence surface degradation processes. The methodology consisted of selecting representative samples, on which macroscopic petrographic analyses were performed, as well as tests of resistance to chemical attack and staining using different chemical reagents and everyday products. Thin sections were prepared, and color and gloss measurements were carried out at the UFC Geology Laboratory in Fortaleza, while petrographic and chemical analyses were conducted at the UFC Crateús’s campus laboratory. Color variations were quantified by colorimetry using the CIE L*a*b* system, and surface gloss was measured before and after chemical attacks, allowing an objective assessment of surface degradation. The results indicated that Bianco Supreme quartzite presents a more homogeneous texture, more compact structure, and lower density of fractures and accessory minerals, whereas Perla Santana shows a higher degree of fracturing and the presence of minerals filling fissures, which increases its susceptibility to fluid percolation and chemical action. Tests demonstrated that, in general, brushed surfaces are more susceptible to staining and gloss loss than polished surfaces. It is concluded that Perla Santana quartzite is more chemically vulnerable than Bianco Supreme, mainly for microstructural rather than purely compositional reasons, highlighting the importance of integrating petrographic characterization and technological tests for the proper specification and use of these materials in architectural projects. Tipo: TCC

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