Banca de QUALIFICAÇÃO: MYLLENA ROSANA DE ARAUJO MEDEIROS

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : MYLLENA ROSANA DE ARAUJO MEDEIROS
DATE: 03/03/2026
TIME: 14:00
LOCAL: Auditório - Química III
TITLE:

Experimental Study on the Impact of Chemical Additives on Carbonate Matrix Acidizing: Emulsion Preventer and Corrosion Inhibitor.

KEY WORDS:

Acid stimulation; Reactive dissolution; Carbonate reservoirs; Chemical additives

PAGES: 80
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Físico-Química
SPECIALTY: Cinética Química e Catálise
SUMMARY:

The reduction in oil well productivity is frequently associated with the formation of damage that compromises the effective permeability of the porous medium. In carbonate reservoirs, matrix acidizing constitutes one of the main remediation strategies, being based on the heterogeneous reaction between hydrochloric acid (HCl) and carbonate minerals, which promotes matrix dissolution and the generation of conductive channels known as wormholes. In operational practice, the acid fluid formulation includes additives such as corrosion inhibitors, employed to protect equipment metallurgy against the high aggressiveness of HCl, and emulsion preventers, responsible for reducing the formation of stable emulsions between the acid and reservoir hydrocarbons. However, the incorporation of these compounds may consequently alter the physicochemical properties of the fluid, indirectly affecting the reaction rate and the mass transport mechanisms involved in carbonate matrix dissolution. This dissertation investigated the influence of the corrosion inhibitor (CI) and the emulsion preventer (EP), individually and in combination (CA), on the rock–fluid interaction during the injection of 15% HCl. The carbonate samples were predominantly composed of calcite, with an average porosity of 18.29 ± 0.01% and an average permeability of 84.89 ± 36 mD. The addition of additives promoted variations in fluid properties, such as density, viscosity, and surface tension, indicating changes in mass transport conditions and in the interfacial energy of the system. Kinetic tests performed at 25 and 60°C indicated that the system containing additives exhibited a lower reaction rate. Under reservoir conditions, EP, CI, and CA resulted in increases in dissolution time of 352%, 2957%, and 1720%, respectively, indicating modification of the kinetic control. In porous media flow tests, the minimum pore volume injected until breakthrough (PVbt) values were 0.30, 0.21, and 0.33 PV for EP, CI, and CA, respectively, demonstrating that adjustments in fluid formulation directly impact the efficiency of acid channeling. Microtomography analysis showed that the formation of dominant wormholes occurred at lower flow rates in acid solutions containing additives compared to those required for 15% HCl without additives. Operation at lower injection rates reduces the pressure differential imposed on the formation, decreasing the likelihood of unintended fracturing. The results demonstrate that additive incorporation, in addition to fulfilling operational functions related to metallurgical protection and emulsion prevention, alters the dissolution kinetics of the carbonate matrix. The observed reaction retardation contributes to improved utilization of the acid agent, reducing the consumption required to reach breakthrough and promoting the formation of more efficient conductive channels under milder operational conditions. Thus, the study demonstrates that acid fluid formulation constitutes a determining variable in reaction kinetics and in the coupling between reaction and transport in porous media, with dissolution rate adjustment being a central element in the optimization of matrix acidizing.

COMMITTEE MEMBERS:
Externo ao Programa - 1752014 - EDNEY RAFAEL VIANA PINHEIRO GALVAO - nullPresidente - 1198847 - JOSE LUIS CARDOZO FONSECA
Externo ao Programa - 1754344 - MARCOS ALLYSON FELIPE RODRIGUES - null