Fuzzy-Based Control System of Drilling Fluids Density and Apparent Viscosity Simultaneously: An Alternative Strategy to Support Autonomous Drilling Operations Thalles P. Mello, Moacyr N. Borges Filho, Rodrigo F. O. Borges, Rodrigo S. C. Ferraz, Alex T. Waldmann, Cláudia M. Scheid, Luiz A. C. Meleiro, Luís A. Calçada SPE Journal, 2024 Summary Among all the systems that make up a drilling operation, the production and correction of drilling fluid can be considered the heart of the process. Among the main objectives of the drilling fluid are to cool the drill bit and maintain the pressure gradient inside the drilling well, which is done by controlling its density. Another important function is transporting the cuttings from the bottom to the surface and keeping them in suspension in case of stoppage, which directly depends on the viscosity of the drilling fluid. Density and viscosity must be constantly maintained within an operational window, and failures can lead to serious accidents, even the loss of the well. Currently, this control is done manually: An operator collects samples of the fluid and takes them for analysis in the laboratory and subsequently makes the necessary corrections by manually adding products to the fluid. To reduce process dead time, keep personnel on board, and increase operation safety, a control and monitoring system is necessary. Fuzzy logic was chosen because it can be combined with classical methods, is cheap to develop and implement, and can be customized in terms of natural language, capturing the knowledge acquired by operators from equipment operation, bench tests, etc. This work aimed to develop a novel real-time monitoring and fuzzy-based system for simultaneous control of the apparent viscosity and density of non-Newtonian fluids, dealing with the inevitable interactions between them in a pilot experimental unit. A pilot plant was built to evaluate the fuzzy system approach for modeling and controlling of density and apparent viscosity of drilling fluids. The pilot flow loop comprises a mixing tank, solids vibrating feeders, and a water-dosing pump. The unit was instrumented with online sensors to measure fluid density, temperature, flow rate, differential pressure, and viscosity. The apparent viscosity and density of the non-Newtonian fluid were controlled by manipulating the dosage of carboxymethylcellulose (CMC), barite, and water. The proposed methodology was compared to a classical proportional-integral-derivative (PID) controller in servo and regulatory scenarios for apparent viscosity and density. The results showed that the fuzzy controller dealt adequately with the effect of variable interactions, keeping both variables within their setpoint ranges, demonstrating the ability to control them individually despite their interactions. These results also showed that the fuzzy-based controller could easily be integrated into a diagnostic-predictive monitoring system to control fluid properties, accomplishing setpoint changes and rejecting undesirable disturbances presenting a maximum overshoot of 7.5% for apparent viscosity and 0.3% for density.
Release of natural extracts from PVA and PVA-CMC hydrogel wound dressings: a power law swelling/delivery Renata Nunes Oliveira, Luiz Augusto da Cruz Meleiro, Brid Quilty, Garrett Brian McGuinness Frontiers in Bioengineering and Biotechnology, 2024 IntroductionPVA hydrogels present many characteristics of the ideal dressing, although without antimicrobial properties. The present work aims to study the physical, mechanical and release characteristics of hydrogel wound dressings loaded with either of two natural herbal products, sage extract and dragon's blood.MethodsFourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) and tensile mechanical testing were used to investigate the structure and properties of the gels. Swelling and degradation tests were conducted according to ISO 10993-9. Release characteristics were studied using UV Spectrophotometry.ResultsPVA matrices incorporating sage extract or dragon's blood (DB) present hydrogen bonding between these components. PVA-CMC hydrogels containing sage present similar spectra to PVA-CMC alone, probably indicating low miscibility or interaction between the matrix and sage. The opposite is found for DB, which exhibits more pronounced interference with crystallinity than sage. DB and NaCMC negatively affect Young's modulus and failure strength. All samples appear to reach equilibrium swelling degree (ESD) in 24 h. The addition of DB and sage to PVA increases the gels' swelling capacity, indicating that the substances likely separate PVA chains. The inclusion of CMC contributes to high media uptake. The kinetics profile of media uptake for 4 days is described by a power-law model, which is correlated to the drug delivery mechanism.DiscussionA PVA-CMC gel incorporating 15% DB, the highest amount tested, shows the most favorable characteristics for flavonoid delivery, as well as flexibility and swelling capacity.
Electrical conductivity measurements and the nonhomogeneous settling behavior of aqueous suspensions of barite Robson Raposa Rocha, Bruno Francisco Oechsler, Cláudia Míriam Scheid, Luís Américo Calçada, Luiz Augusto Meleiro Aiche Journal, 2022 Using electrical conductivity measurements to monitor the local concentration of solids indirectly in settling tests is a practice already explored in the literature. However, since suspended particles may comprise a mixture of solids, a new suspension preparation methodology and calibration procedure were proposed to eliminate the influence of soluble materials on conductivity measurements. This article investigates water‐barite suspensions of 10%, 15%, and 20% v/v in solids. Their settling dynamics resulted in particle Reynolds numbers and Peclet numbers always smaller than 0.0012 and larger than 2100, respectively. Particle agglomeration, multiple boundaries (layers of different maximum local concentrations), channeling (formation of flow paths or channels), and particulate stratification were some phenomena inferred from the results. Hence, this article illustrates that settling behaviors typically seen in solid–liquid mixtures of non‐Newtonian continuous phase can also occur in aqueous suspensions, indicating there are still considerable challenges to understanding the process of gravitational settling.
Estimation of expanded uncertainty associated to analysis of reducing sugars by Lane-Eynon method Boletim Centro De Pesquisa De Processamento De Alimentos, 2014
Constructive Neural Network in Model-Based Control of a Biotechnological Process Proceedings of the International Joint Conference on Neural Networks, 2003
A complete model for oxidation air-lift reactors E. Camarasa, L.A.C. Meleiro, E. Carvalho, A. Domingues, R. Maciel Filho, G. Wild, S. Poncin, N. Midoux, J. Bouillard Computers and Chemical Engineering, 2001
A hydrodynamic model for air-lift reactors E. Camarasa, E. Carvalho, L.A.C. Meleiro, R. Maciel Filho, A. Domingues, G. Wild, S. Poncin, N. Midoux, J. Bouillard Chemical Engineering and Processing, 2001
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