Nilesh Kumar Jha1, Anastasia Ivanova2, Maxim Lebedev3, Ahmed Barifcani3, Alexey Cheremisin4, Stefan Iglauer5, Jitendra S Sangwai6, Mohammad Sarmadivaleh3. 1. Western Australian School of Mines (WASM): Minerals, Energy and Chemical Engineering, Curtin University, 26 Dick Perry Avenue, Kensington, Western Australia 6151, Australia; Petroleum Engineering Program, Department of Ocean Engineering, Indian Institute of Technology Madras, Chennai, Tamil Nadu 600036, India. Electronic address: nilesh.jha@spt.pdpu.ac.in. 2. Western Australian School of Mines (WASM): Minerals, Energy and Chemical Engineering, Curtin University, 26 Dick Perry Avenue, Kensington, Western Australia 6151, Australia; Skolkovo Institute of Science and Technology, Moscow 121205, Russia. 3. Western Australian School of Mines (WASM): Minerals, Energy and Chemical Engineering, Curtin University, 26 Dick Perry Avenue, Kensington, Western Australia 6151, Australia. 4. Skolkovo Institute of Science and Technology, Moscow 121205, Russia. 5. School of Engineering, Edith Cowan University, 270 Joondalup Drive, Joondalup, Western Australia 6027, Australia. 6. Petroleum Engineering Program, Department of Ocean Engineering, Indian Institute of Technology Madras, Chennai, Tamil Nadu 600036, India.
Abstract
HYPOTHESIS: The advanced low salinity aqueous formulations are yet to be validated as an injection fluid for enhanced oil recovery (EOR) from the carbonate reservoirs and CO2 geosequestration. Interaction of various ionic species present in the novel low salinity surfactant nanofluids with scCO2/CO2 saturated aqueous phase interface and at the interface of CO2 saturated aqueous phase/mixed wet (with CO2 and Decane) limestone surface at the conditions of low salinity at reservoir conditions are to yet to be understood. EXPERIMENTS: This study, carried out for the first time in low salinity at scCO2 loading conditions at 20 MPa pressure and 343 K temperature, comprises of wettability study of the limestone surface by aqueous phase contact angle measurements using ZrO2 nanoparticles (in the concentration range of 100-2000 mg/L) and 0.82 mM Hexadecyltrimethylammonium bromide (CTAB) surfactant. Molecular dynamics simulations results were used to understand the underlying mechanism of wettability alteration and interfacial tension (IFT) change. FINDINGS: This study reveals that a low dosage (100 mg/L) of ZrO2 nanoparticles forming ZrO2-CTAB nano-complexes helps in wettability alteration of the rock surface to more water-wetting state; certain ionic species augment this effect when used in appropriate concentration. Also, these nano-complexes helps in scCO2/CO2 saturated aqueous phase IFT reduction. This study can be used to design advanced low salinity injection fluids for water alternating gas injection for EOR and CO2 geosequestration projects.
HYPOTHESIS: The advanced low salinity aqueous formulations are yet to be validated as an injection fluid for enhanced oil recovery (EOR) from the carbonate reservoirs and CO2 geosequestration. Interaction of various ionic species present in the novel low salinity surfactant nanofluids with scCO2/CO2 saturated aqueous phase interface and at the interface of CO2 saturated aqueous phase/mixed wet (with CO2 and Decane) limestone surface at the conditions of low salinity at reservoir conditions are to yet to be understood. EXPERIMENTS: This study, carried out for the first time in low salinity at scCO2 loading conditions at 20 MPa pressure and 343 K temperature, comprises of wettability study of the limestone surface by aqueous phase contact angle measurements using ZrO2 nanoparticles (in the concentration range of 100-2000 mg/L) and 0.82 mM Hexadecyltrimethylammonium bromide (CTAB) surfactant. Molecular dynamics simulations results were used to understand the underlying mechanism of wettability alteration and interfacial tension (IFT) change. FINDINGS: This study reveals that a low dosage (100 mg/L) of ZrO2 nanoparticles forming ZrO2-CTAB nano-complexes helps in wettability alteration of the rock surface to more water-wetting state; certain ionic species augment this effect when used in appropriate concentration. Also, these nano-complexes helps in scCO2/CO2 saturated aqueous phase IFT reduction. This study can be used to design advanced low salinity injection fluids for water alternating gas injection for EOR and CO2 geosequestration projects.