Experimental study on foamy oil behavior using a heavy oil‒methane system in the bulk phase

New foamy oil behavior, which is presented as relative volume changes of foamy oil over time, is researched in this study. The experimental results indicate that similar trends and phenomena are investigated for both constant pressure depletion rate test and constant volume withdraw rate test. For solution gas phase, the concentration of solution gas has a strong exponential relationship with time. In addition, the reaction rate constant kSG which indicates the gas transfers rate from solution gas to dispersed gas, increases with the depletion/withdraw rate increases. For free gas phase, moles of the evolved free gas proportional to t1/2, and the same relation is observed in step-by-step test. Furthermore, the pseudo-bubble point pressure decreases with the depletion/withdraw rate increases, and a new approach using the trendlines of the moles of free gas versus t1/2 is developed to determine the time when the pseudo-bubble point pressure achieves.