Jingwen (Jessica) Cui
Research topic: “Retrieval of Solvent Injected During Heavy-Oil Recovery in Heterogeneous Porous Media: Pore Scale Analysis through Micro Model Experiments"
Solvent retrieval is essential for the economics of the solvent-related heavy-oil recovery technologies. In fractured and oil-wet reservoirs, water-flooding followed by solvent is not suitable to achieve this goal. Two methods can be proposed as solution to solvent retrieval in complex reservoirs: (1) Thermal: Hot water or steam injection to vaporize the solvent; (2) Chemical: Addition of surface active agents to alter wettability for effective matrix-fracture transfer
This research aimed to investigate the mechanics of these two methods at the pore-scale. A series of experiments using heterogeneous micro-models were designed for this purpose. The process of solvent vaporization and entrapment during heating followed by solvent injection was evaluated using the images obtained from the experiments. Evaluations were made using the parameters (pore size, wettability, interfacial tension, and solvent type) in the Thomson equation. The nucleation of solvent and the distribution of fluids/phases emerged through this process were qualitatively analyzed. Suitable application conditions (temperature, heating source location) for different solvent types and wettability were determined.
Next, selected chemicals (conventional surfactants and new generation –nano-chemicals) were tested as an alternative to solvent injection to recover heavy-oil and as a material to retrieve the solvent instead of applying heat injection methods. Proper chemical types were identified for effective solvent retrieval and heavy-oil recovery from different wettability conditions and solvent types.
Cui, J. and Babadagli, T.: “Solvent Retrieval during Miscible Flooding in Heterogeneous Reservoirs Using New Generation Nano EOR Materials: Visual Analysis through Micro Model Experiments,” SPE 181320, 2016 SPE Ann. Tech. Conf. and Exh., Dubai, UAE, 26-28 Sept.
Cui, J. and Babadagli, T.: “Retrieval of Solvent Injected During Heavy-Oil Recovery from Water- and Oil-Wet Reservoirs: Pore Scale Analysis at Variable Temperature Conditions,” SPE 181166, 2016 SPE Latin America and Caribbean Heavy and Extra Heavy Oil Tech. Conf., Lima, Peru, 19-20 Oct.