Micromodel foam floods

The PS micromodel, on the other hand, had fewer pore connections, and the pores were of more uniform size consequently, it was almost completely swept of liquid in the GDS foam flood (Test... 

The available literature shows that foams can reduce gas mobility in porous media but are sensitive to the presence and saturation level of residual oil. Several of the core-flood studies suggest that incremental oil recovery may be possible because of foam-flooding, and that oil-in-water emulsions may be formed in the process (24, 25, 39, 40). There have also been relatively few attempts to connect core-flood results with micromodel studies and basic physical properties. 

The emulsification—imbibition of oil into foam, which the lamella number is intended to describe, has been noticed or predicted by a number of authors and was illustrated in Chapter 2. Lobo et al. (50) emphasized the importance of this phenomenon for foam stability. Rater-man (28) predicted that emulsification—imbibition would be important in constant quality preformed foam injection floods. In the core-flood studies of French et al. (54), they observed that the contacting of foam with crude oils produced emulsified droplets of oil within the foam lamellae. Schramm et al. (40) determined MRFs for a number of foams flowing in Berea sandstone cores containing residual light crude oil and found a strong correspondence with the micromodel results (Figure 10). This work was the first to show that foams that are quite stable to oil in the micromodel are also quite effective in core-floods and vice versa. 

---