Experimental measurement and modeling of the solubility and bubble pressure of nitrogen in white mineral oil

摘要

Before using oil-based drilling fluid (OBDF) in gas-lift dual gradient drilling (DGD), the pressure-volume-temperature (PVT) behavior of gas/OBDF mixture must be known. The main objective of this study is to figure out the PVT behavior of nitrogen and white mineral oil (#5) by experimental determination of such properties as the bubble pressure and solubility. These measurements were conducted in a window PVT cell apparatus by using constant composition expansion method. The conditions of experiment were planned for common riser conditions, pressure up to 3600psi and temperature in the range of 68-176 degrees F. Novel bubble pressure and solubility models were proposed. Moreover, these models were compared to the conventional black oil correlations.