Resumen de Evaluation of changes in macerals and geochemical properties during hydrocarbon generation based on pyrolysis of lignite from Mainland China
In this study, we adopted thermal simulation to explore the changes of macerals compositions and trace elements in the coal oil processing. Using lignite for the thermal simulation, the changes of various parameters and trace elements in the thermal evolution were explored. The experimental results showed that the content of vitrinite decreased gradually with increasing thermal maturity, where both types of macerals components were developing into inertinite, mainly fusinite and semifusinite. The Pr/Ph value of lignite has decreasing trend under the thermal maturation process. Trace elements that have catalytic effect are Cr, Cu, and Zn; the relative contents of the three trace elements all have increasing trend with rising thermal maturation evolution. Lignite at simulated temperature of 350 °C has the highest yield of oil and gas. When Ro% is approaching nearly 1.37, there is better yield of oil and gas. From the simulations, it is known that the critical temperature of the lignite is near 350 °C and its corresponding Ro% is 1.37. The changes in the relative contents of the catalytic trace elements (Zn, Cu, Cr) and yield performance of oil and gas, approaching 350 °C temperature will be a turning point of thermal maturation.
