Assessment of hydrocarbon generation potential of bituminous coal from Raniganj Basin, India

ABSTRACT

The present work deals with a study based on the geochemical techniques such as Rock-Eval pyrolysis, total organic carbon content (TOC), and detailed petrographic study to assess hydrocarbon generation potential of coal. A graph between TOC against hydrogen index (HI) has been plotted to detect the type of generating hydrocarbon, which lies in fair oil source. The significant amount of TOC and HI supports the formation of hydrocarbon. The vitrinite reflectance value and T_max (431°C–446°C) also confirm that samples are matured enough to generate liquid and gaseous hydrocarbon in coal. The coal samples also contain sufficient quantity of vitrinite and liptinite macerals varying from 70.28% to 75.41 wt%, which confirm the production of liquid hydrocarbon. The cross-plot between H/C and O/C atomic ratio indicates that samples were predominant in the bituminous rank and having kerogen Type III makes it suitable for hydrocarbon generation. Similar results were found in Rock-Eval pyrolysis analysis (Types II-III and Type III kerogen). Seyler’s diagram reveals that most of the samples are per-hydrous in nature.

KEYWORDS:

• TOC
• Pyrolysis temperature
• thermal maturity
• petrography
• oil yield