Table 2: Recovery of each scheme during different stages.

Scheme number Polymer injection scheme Oil recovery during different stages (%)
Concentration
(mg/L)
Injection time
(h)
Front water flooding Polymer flooding Subsequent water flooding Total
1-1 2000 3 51.28 20.15 2.39 73.82
1-2 2000 1 50.84 28.36 2.17 81.37
1600 2
800 1