https://repositorio.ufpb.br/jspui/handle/123456789/11874 PPGEQ Thu, 22 Oct 2026 12:22:45 GMT 2026-10-22T12:22:45Z https://repositorio.ufpb.br/jspui/handle/123456789/39457 Título: Integração de controladores preditivos de modelos econômicos e otimização em tempo real aplicados uma planta de captura de carbono Autor(es): Diniz Filho, Jose Carlos Orientador: Morais Júnior, Arioston Araújo de Abstract: The mitigation of carbon dioxide (CO₂) emissions resulting from the combustion of fossil fuels represents one of the major technological and environmental challenges of modern society. In this context, Carbon Capture and Storage (CCS) systems have been extensively investigated, particularly post-combustion processes based on chemical absorption with amines, due to their technological maturity and potential for integration into existing industrial plants. However, the high energy consumption and operational costs associated with these systems still limit their large-scale deployment, highlighting the need for advanced modeling, control, and optimization strategies. In this study, an integrated architecture combining Model Predictive Control (MPC) with economic objectives and Real-Time Optimization (RTO) is developed, implemented, and evaluated for a post-combustion CO₂ capture plant based on chemical absorption with monoethanolamine (MEA), rigorously simulated in Aspen Plus Dynamics®. Initially, dynamic simulation of the plant was performed, followed by the application of pseudo-random binary sequence (PRBS) excitation signals to generate data for the identification of linear multivariable process models. Based on these data, output-prediction oriented models (OPOM) were developed, and CLMPC and IHMPCFF controllers were implemented to dynamically track the economic targets defined by the RTO layer. In addition, a Kalman filter was incorporated for the estimation of non-measurable states, providing improved predictive accuracy and eliminating steady-state offset. The MPC controllers were subsequently integrated with a higher-level steady-state model-based economic optimization layer (RTO), responsible for periodically recalculating the optimal operating points while accounting for energy costs, CO₂ pricing, solvent consumption, and environmental penalties. The results demonstrate that the integrated RTO–MPC framework leads to significant improvements in energy efficiency, enhanced dynamic stability, and reduced operational costs under variations in load and flue gas composition. These findings confirm that the integration of predictive control and economic optimization constitutes a promising approach for the sustainable and economically viable operation of industrial CO₂ capture plants. Editor: Universidade Federal da Paraíba Tipo: Dissertação Thu, 26 Feb 2026 00:00:00 GMT https://repositorio.ufpb.br/jspui/handle/123456789/39457 2026-02-26T00:00:00Z https://repositorio.ufpb.br/jspui/handle/123456789/38619 Título: Análise de desempenho de controladores preditivos com estratégia Hot Vapor Bypass em um processo de Destilação com Oscilação de Pressão (PSD) Autor(es): Soares, Priscila Veloso Nogueira Orientador: Morais Júnior, Arioston Araújo de Abstract: Pressure-swing distillation (PSD) is a promising alternative for the separation of azeotropic mixtures, such as acetonitrile–water, but its operation involves significant challenges due to strong variable coupling, nonlinearities, and sensitivity to disturbances. In this context, this work evaluated the performance of different predictive control strategies in a PSD plant with full heat integration and the use of the hot vapor bypass (HVP) strategy, applied to assist pressure control and improve stability and energy efficiency. Concepts related to azeotrope formation, separation strategies, pressure control alternatives, and the characteristics of conventional and predictive controllers, particularly the Extended Infinite Horizon Model Predictive Control (EIHMPC) and its variation with implicit feedforward action (EIHMPCFF), were explored in the theoretical framework. The process was simulated using Aspen Plus™ and Aspen Dynamics™, followed by dynamic model identification through open-loop disturbances and the development of multivariable models implemented in MATLAB®, where PID, LMPC, EIHMPC, and EIHMPCFF controllers were tested. Comparative analyses considered scenarios of disturbances in the feed to the low-pressure column and setpoint changes, evaluating response time, and disturbance rejection. The results showed that LMPC achieved better performance than PID, although it still presented steady-state deviations; EIHMPC corrected these limitations, ensuring greater stability and accuracy; and EIHMPCFF stood out by anticipating disturbance effects, providing faster responses with lower accumulated error. Therefore, it is concluded that EIHMPCFF was the best-performing controller, confirming the relevance of advanced predictive strategies for complex industrial processes. Editor: Universidade Federal da Paraíba Tipo: Dissertação Thu, 31 Jul 2025 00:00:00 GMT https://repositorio.ufpb.br/jspui/handle/123456789/38619 2025-07-31T00:00:00Z https://repositorio.ufpb.br/jspui/handle/123456789/38618 Título: Caracterização de fluido de perfuração emulsionado e seu impacto na microbiota do solo Autor(es): Silva, Jénifer Laís Herculano da Orientador: Curbelo, Fabiola Dias da Silva Abstract: This study investigated components of emulsion-based drilling fluids, aiming to identify sources of contamination and assess their impact on soil microbiota. To minimize environmental damage, two sustainable fluids were formulated using mollusk shell powder (MSP) as a filtrate reducer and saponified coconut oil (SCO) as a surfactant. The combination of these components ensured a stable emulsion and a reduction in filtrate volume without significantly compromising the viability of soil microorganisms. Microbiological analysis indicated that MSP and the viscosifying aqueous solution (GX) were the main contaminants, with results of 5.50×10² and 1.31×10⁵ CFU/mL respectively, while SCO exhibited bactericidal activity, with no microbial growth observed on the analyzed plates, contributing to reduced microbiological contamination. The fluids were tested in estuarine soil in accordance with ABNT NBR 10007:2004 standards, ensuring sample integrity. The results showed that the use of these bio-based additives in drilling fluids is an environmentally friendly alternative with no significant adverse effects on the viability of soil microorganisms. Thus, it was concluded that MSP and SCO are sustainable options for drilling fluid formulation, in compliance with current environmental regulations and the principles of the circular economy. Editor: Universidade Federal da Paraíba Tipo: Dissertação Thu, 03 Jul 2025 00:00:00 GMT https://repositorio.ufpb.br/jspui/handle/123456789/38618 2025-07-03T00:00:00Z https://repositorio.ufpb.br/jspui/handle/123456789/38616 Título: Aplicação de biorreatores anaeróbios de membranas no tratamento biológico da água produzida do petróleo para produção de biogás Autor(es): Marinho, Camilla Eduarda Dias Orientador: Sena, Rennio Felix de Abstract: The produced water, a significant byproduct of oil extraction, represents a major environmental challenge due to its complex composition and high pollution potential. This study investigated the application of anaerobic membrane bioreactors (AnMBRs) in treating this effluent, evaluating their efficiency in removing organic contaminants and producing biogas. AnMBRs combine anaerobic digestion with membrane filtration, standing out for their low energy consumption, reduced sludge production, and potential for resource recovery. Factors such as pH (maintained between 6.4 and 7.0), temperature (32-35 ºC), and organic load were monitored to optimize microbial performance and biogas production. The experiment was divided into four phases, starting with 100% domestic sewage, followed by 20% produced water mixed with 80% domestic sewage, then a 50% mix of each, and concluding with 100% produced water, allowing gradual adaptation of the AnMBR microbiota. The results demonstrated high system efficiency, with organic matter removal exceeding 81% for COD and BOD, and over 94% for TSS. Biogas production varied between 0.25 and 0.35 m³ CH₄/kg COD, with a range in methane composition from 35% to 74%. In addition to meeting standards, the process proved promising for mitigating environmental impacts in the oil industry and other industrial sectors, reinforcing its contribution to the sustainable management of resources. Editor: Universidade Federal da Paraíba Tipo: Dissertação Wed, 30 Jul 2025 00:00:00 GMT https://repositorio.ufpb.br/jspui/handle/123456789/38616 2025-07-30T00:00:00Z