A simulation case study—the Brent Sands

1 The relative permeability curves used as in Sorbie etal. (1982). They differ between five different rock types in the reservoir 

Polymer solution viscosity varies with concentration as  

For the Brent Sands section described above, it was found that oil production from the medium- and low-permeability layers followed distinctive patterns (Clifford and Sorbie, 1984, 1985), Seventy per cent of the total incremental oil was produced from the low-permeability layers, the sweeping taking place over a relatively short period of pressure enhancement ( 1-2 years) following polymer injection. The remaining 30% came from the medium-permeability layers, where incremental oil recovery was still 

A detailed analysis of the recovery mechanism in this system has been carried out (Clifford and Sorbie, 1984, 1985), and the cross-flow mechanisms mentioned in the previous section have been shown to apply. However, the analysis is quite lengthy and the reader is referred to this earlier work. Also, the mechanisms will be illustrated much more clearly using results from the calculations presented in the following subsection. This example is presented here as a suitable real-field illustration of the effects of polymer flooding in stratified systems. This example will be considered again when discussing the effects of polymer adsorption and degradation. 

---