The Impact of Adsorbed Triethylene Glycol on Water Wettability of the {1014} Calcium Carbonate Surface
Abstract
Water flooding is increasingly being used as a method of enhanced oil recovery and frequently involves calcium carbonate reservoirs. Very often, thermodynamic conditions in the upper few hundred meters allow for hydrate formation. One possible method of preventing hydrates is to inject hydrate inhibitors such as triethylene glycol (TEG) into the reservoir. Thus, it is of importance to know how such glycols affect water wettability, which is an important factor defining the oil behavior in such reservoirs. Wettability of a surface is defined by the contact angle of a liquid drop on the surface. The stronger the liquid is attracted to the surface, the smaller the wetting angle becomes, implying an increased degree of wetting. Therefore, it is possible to gain qualitative knowledge of the change in wetting properties with respect to external influences by studying corresponding changes in free energy of adsorption of the liquid. In our work [1], we used molecular dynamics (MD) and Born-Oppenheimer molecular dynamics (BOMD) to study how adsorbed TEG on the {1014} calcium carbonate surface affected adsorbed water. We used the changes in density profiles of water to estimate changes in adsorption free energy of water. The adaptive biasing force (ABF) method was applied to TEG to calculate the adsorption free energy of TEG on the calcium carbonate surface. We found that water wetting of the calcium carbonate surface decreased in the presence of adsorbed TEG. [1] - Olsen, R.; Leirvik, K.; Kvamme, B.; Kuznetsova, T. Adsorption Properties of Triethylene Glycol on a Hydrated {1014} Calcite Surface and Its Effect on Adsorbed Water, Langmuir 2015, DOI: 10.1021/acs.langmuir.5b02228
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2015
- Bibcode:
- 2015AGUFMMR41D2677O
- Keywords:
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- 1859 Rocks: physical properties;
- HYDROLOGY;
- 5120 Plasticity;
- diffusion;
- and creep;
- PHYSICAL PROPERTIES OF ROCKS;
- 5199 General or miscellaneous;
- PHYSICAL PROPERTIES OF ROCKS;
- 8118 Dynamics and mechanics of faulting;
- TECTONOPHYSICS