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EVALUATION OF GAS DUMPFLOOD IN WATER-FLOODED RESERVOIR |
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| รหัสดีโอไอ | |
| Title | EVALUATION OF GAS DUMPFLOOD IN WATER-FLOODED RESERVOIR |
| Creator | Natdanai Urairat |
| Contributor | Suwat Athichanagorn |
| Publisher | Chulalongkorn University |
| Publication Year | 2557 |
| Keyword | Oil field flooding, Oil reservoir engineering |
| Abstract | Gas dumpflood in water-flooded reservoir is a method to increase oil recovery by dumping gas from a gas reservoir underneath into the subject oil reservoir after initial period of water flooding. In this study, six design parameters are investigated to determine the suitable strategy of this method. The best well arrangement for 0 dip angle is two horizontal producers with 2,000 ft distance between producers and the vertical injector. For 15° and 30° dip angle, the best well arrangement is one horizontal producer with 4,000 ft distance. Using of 1% water cut criteria yields the best production strategy. The perforation interval of gas reservoir of 0 dip angle is 20% interval from bottom. For 15° and 30° dip angle, perforation interval cannot be varied due to fracture pressure. The best water injection and production rates of 0 dip angle are 3,000 and 7,000 STB/D, respectively. For 15° and 30° dip angle, different combinations of both water injection and liquid production rates yield comparable results. For sensitivity analysis, lower kv/kh ratio of 0° dip angle slightly increases oil recovery but too low ratio moderately reduces oil recovery due to the fact that oil cannot move down to producers. For 15° dip angle, there is insignificant difference of oil recovery among different anisotropy ratios. For 30° dip angle, higher ratio slightly increases oil recovery. In term of gas thickness, higher gas thickness slightly increases oil recovery for 0° and 30° dip angle. For 15° dip angle, oil recovery moderately increases. Higher depth difference between oil and gas reservoir slightly increases oil recovery except for the case of 3,000 ft depth difference of 0° dip angle due to skin factor. In term of Sorw, the lower the residual oil, the higher the oil recovery except for the case of 30° dip angle that the results show no trend. The reduction of Sorg shows moderately higher oil recovery than the reduction of Sorw. Lower oil recovery is obtained when original oil viscosity increases. |
| URL Website | cuir.car.chula.ac.th |
