Table 7
Optimization results for each adjusted variable in the common water injection and engineered salinity.
| Case | INJ-rate | INJ-press | PRD-rate | PRD-press | Ca2+ | SO4 2− | Mg2+ | EW-mod | NPV | ΔNPV |
|---|---|---|---|---|---|---|---|---|---|---|
| m3/day | kPa | m3/day | kPa | (ppm) | (ppm) | (ppm) | (MMUS$) | (MMUS$) | ||
| Water | 4988.29 | 33 919.73 | 1996.66 | 17 943.14 | – | – | – | – | $16.95 | – |
| EW-25 | 4866.87 | 33 087.09 | 1961.96 | 17 353.35 | 7127.23 | 5420.62 | 1033.83 | 3 | $66.57 | $49.62 |
| EW-75 | 4940.44 | 33 591.59 | 1982.98 | 17 710.71 | 7333.23 | 6627.23 | 1975.58 | 3 | $58.54 | $41.60 |
| EW-300 | 4975.48 | 33 831.83 | 1992.99 | 17 880.88 | 8931.33 | 8038.64 | 739.54 | 3 | $24.69 | $7.74 |
| EW-500 | 4898.4 | 33 303.3 | 1970.97 | 17 506.51 | 8715.52 | 8401.6 | 1661.66 | 3 | $8.22 | −$8.73 |