Programa de Pós-Graduação em Engenharia Química - PPGEQ/ITEC
URI Permanente desta comunidadehttps://repositorio.ufpa.br/handle/2011/2308
O Programa de Pós-Graduação em Engenharia Química (PPGEQ) do Insituto de Tecnologia (ITEC) da Universidade Federal do Pará (UFPA). Sendo aprovado pela CAPES / MEC em 1991, foi oficialmente iniciado em março de 1992.
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Navegando Programa de Pós-Graduação em Engenharia Química - PPGEQ/ITEC por Assunto "Acidificação matricial"
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Item Acesso aberto (Open Access) Influência do transporte advectivo no processo de dissolução de rochas carbonáticas em ácido clorídrico.(Universidade Federal do Pará, 2024-04-30) COSTA, Brenda Matos da; SILVA, Daniel; AUM, Pedro Tupã Pandava; http://lattes.cnpq.br/7515419219571335Carbonate rock stimulation is a technique used in the petroleum industry to increase the productivity index of wells by increasing the permeability of a region close to the well. In acidification, an acid is injected into the reservoir rock. In carbonate rocks, the acid interacts with the rock to promote dissolution. The acid-rock occurrence is characterized by being essentially heterogeneous due to the different phases of the reactants. The quantification of occurrence taxa in heterogeneous systems is complex, as it involves a combination of several variables that are relevant to the manifestation of transport. The way in which acid interacts with the porous medium can be analyzed using various techniques and equipment that can help with understanding. The most common equipment is the Rotating Disk Apparatus (RDA), which consists of a reactor, which can operate different pressure and temperature ranges and different rotations. However, due to the difficulty of acquiring this type of equipment, several experiments have been reported using alternative methodologies. Thus, this work aims to study how measuring the reaction rate using different methodologies can influence the result. A comparative experimental study was conducted using three different methodologies, namely, static dissolution, dynamic dissolution, and rotating disk, to measure the impact of mineralogy, porosity, rotation speed, and pressure applied to the reaction system. The focus is to evaluate to what extent the results of the static and dynamic dissolution experiments diverge from the experiments conducted with the rotating disk, which is considered the standard for this type of analysis. In general, it was observed that increasing rotation promotes an increase in the reaction rate of 10.36% from static to dynamic at 100 RPM and 63.07% from static to dynamic at 500 RPM for Indiana limestone, a similar behavior was observed for other mineralogies. Additionally, from obtaining the diffusion coefficient in the process of dynamic dissolution and rotating disk of 3.75x10^-5 and 9.13x10^-5, respectively, for coquina samples, it was evidenced that the absence of pressure in the system hinders the mass transfer process due to the presence of CO2 (g), thus underestimating the diffusion in the carbonate – HCl system.Item Acesso aberto (Open Access) Simulação numérica da acidificação de carbonatos utilizando malhas obtidas a partir de imagens de MICRO-CT(Universidade Federal do Pará, 2024-05-21) SANTANA, Beatriz dos Santos; VICENTE, Bruno José; http://lattes.cnpq.br/4190693236960837; AUM, Pedro Tupã Pandava; http://lattes.cnpq.br/7515419219571335Matrix acidizing is one of the well stimulation techniques that consists of pumping an acid solution at a pressure lower than the fracture pressure of the rock. In carbonate formations, as a result of the acid-calcite reaction, part of the rock is dissolved and high conductivity channels, called wormholes, are created. One of the major challenges associated with simulating this type of process is to incorporate the heterogeneities inherent in carbonate rocks into the numerical meshes. The main objective of this work is to simulate acidification in carbonate rock plugs using the initial porosity field obtained from a microCT image. Two-scale modeling was used, with the balance of the amount of movement carried out using the Navier-Stokes-Brinkman approach. The simulations were carried out in a code developed in openFOAM, varying the speed of the acid on the face and obtaining the PVbt (Pore Volume to Breakthrough) for each condition. Mesh convergence analyses and the impact of varying the inlet interstitial velocity were carried out. Simulation results were compared with initial porosity fields generated using the uniform, normal and lognormal distributions. The initial porosity and permeability distributions obtained were consistent with the microCT image. Variations in the number of cells had no significant impact on the PVbt. By varying the injection speed on the face, it was possible to obtain the uniform, conical, branched, dominant wormhole, dissolution on the face and compact dissolution patterns, obtaining the PVbt curve to determine the optimum point (lowest PVbt). For the model developed from the image, the lowest PVbt obtained was 0.262 with an input speed of 4 2,12 10 m/s − . For the models with uniform, normal and lognormal porosity distributions, the lowest PVbt values obtained were 0.276, 0.261 and 0.309 at an input speed of 5 8,3 10 m/s − . The results presented showed that the methodology used to obtain porosity fields from microCT images can be used to obtain results that are more representative in terms of accounting for rock heterogeneities.