Application of Quantitative HTGC and HTGC-MS to Paraffin-Based Production Problems
D. A. Wavrek and N. F. Dahdah
Crude oils with high pour points and undesired flow properties have been documented in a variety of geologic provinces; a condition that is frequently attributed to paraffin or wax. Previous attempts to characterize this high molecular weight (HMW; nC40+) material was limited to bulk methods, although recent advances in analytical technologies allow this fraction to be separated into individual components by high temperature gas chromatography (HTGC) and mass spectrometry (HTGC-MS). The latter technique is particularly powerful for compound identification, whereas the quantitative aspects provide a predictive parameter for mass balance applications.
HTGC data from a global database indicate that a diverse assemblage of organic compounds contribute to the C40+ fraction. Furthermore, this fraction can exhibit quantitative variation over several orders of magnitude within genetically-related oils. Individual case studies demonstrate that this variation can be due to natural in-situ reservoir processes (phase separation, gravity segregation) or be attributed to anthropogenic petroleum recovery activities. This technology can be used to develop more efficient production strategies and allow more accurate forecasting of recovery volumes and costs.
AAPG Search and Discover Article #91019©1996 AAPG Convention and Exhibition 19-22 May 1996, San Diego, California