Experimental study of carbonate rock-oil-acid solution in the oil well acidizing from a molecular and macroscopic points of view

Boustani, Leili; Saeedi Dehaghani, Amirhossein; Karami, Saeed; Salehi, Nowzar

doi:10.24200/sci.2024.63627.8505

Experimental study of carbonate rock-oil-acid solution in the oil well acidizing from a molecular and macroscopic points of view

Document Type : Article

Authors

¹ Petroleum Engineering Department, Faculty of Chemical Engineering, Tarbiat Modares University, Tehran, Iran

² Petroleum Engineering & Development Company (PEDEC), Tehran, Iran

10.24200/sci.2024.63627.8505

Abstract

This study addresses the rock-fluid interactions in the carbonate rock acidizing from molecular and macroscopic insights. After treating the aged rock slices, the desorbed hydrocarbon chemistry, wettability alteration, and rock dissolution were studied by using the ATR–FTIR technique, contact angle measurement, and weight loss calculation. To investigate the effect of companying ions on the acidizing, the acid solutions were prepared with various dissolving salts (NaCl, Na2SO4, MgCl2, and CaCl2 ) and HCl concentrations. The acid solutions (concentrations of 0.05% and 0.2%) with a base of distilled water showed a higher rock dissolution respect to the ones with a brine water base. The weakest dissolution was observed in the solution with the formation water base, showing the inhibition effect of formation water on dissolution. The acidizing of the aged rock slice increased the rock hydrophilicity. Based on the contact angles, the Na2SO4 and KCl are prohibiting agents for hydrocarbon desorption. According to ATR-FTIR characteristic indexes, aromatic hydrocarbons have a greater desorption respect to the aliphatic ones. The asphaltenes have a higher potential to be desorbed from the rock surface in the acidizing. It was shown that the NaCl and CaCl2 were more feasible for desorbing the aromatic hydrocarbons.

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