Advancing Real-Time Fluid Characterization: A Novel Approach to Determine Extraction Efficiency Correction in Advanced Mud-Gas Services

The extraction efficiency correction (EEC) is a method that is used in conjunction with advanced mud-gas services (AGAS). This correction method is the uppermost layer for the mud-gas data correction and critical for fluid compositional analysis and fluid type interpretation, as well as for achieving PVT-like data in real-time. The extraction correction factors are individually determined for each hydrocarbon gas component from Methane to N-Pentane, since each component has different individual physical properties.

Until now, the present AGAS equipment has the capability to carry out this test with a live sample from an active drilling process in a timespan of 15minutes. Since a minimum concentration level of 10 ppm per compound is required for the EEC, most often this test is possible only while drilling reservoir or, in case that the client is not willing to give up reservoir data, after reaching total depth of the well. These limitations required the development of an enhanced method to enable an extraction characterization of the equipment for a certain mud type at any point in time if drilling mud is available.