Abstract:

Water alternating gas injection - WAG is a method of rotating water injection with gas to reduce gas mobility and increase efficiency enhanced oil recovery. Compared with other methods of enhanced oil recovery - EOR (Enhanced Oil Recovery), gas injection is a method in accordance with the conditions of the Miocene formation, White Tiger field for EOR stage. Experimental results shown that, when using separated gas injection to push the oil, the minimum miscible pressure between gas and oil is 350 bar. Results of simulation model running on CMG simulator shown that to achieve conditions mixed with oil at current reservoir pressure is 280 bar, injection gas must be enriched to 40% low-pressure gas or 17% liquefied natural gas that of this gas is burned off should be collected. Experimental results of WAG injection on combined core samples shown that given oil recovery efficiency of WAG injection up to 80.2% compared to 60.5% of water injection. After water injection, WAG application may recover additional 17.8% of the original oil in place. WAG injection can only be successfully applied to the formation Miocene, Bach Ho field when gas supply source for gas injection and enrichment resources is resolved