Evaluation of kinetic parameters by thermogravimetric analysis of shale in muerto formation, Talara-Peru

Pretell V.; Ubillas C.; Ruiz C.; Rodriguez J.; Ramos W. · Proceedings of the LACCEI international Multi-conference for Engineering, Education and Technology (2020) · DOI: 10.18687/laccei2020.1.1.70

Resumen

Shale is a fine-grained sedimentary rock composed of minerals and organic matter from which oil can be obtained through thermochemical processes such as pyrolysis. The Muerto formation is located in the Lancones Basin, Peru, which has favorable geological and geochemical characteristics that indicate the existence of shale rocks with unconventional oil potential. Chemical characterization and kinetic analysis of three shale samples were performed to assess their potential as a source of liquid fuels. The elemental analysis indicates an H/C ratio in the range of 0.45 to 1.13. The organic matter content analyzed by the Walkley & Black method varies between 5.60 to 7.03% (m/m) and from 1.65 to 3.40% (m/m) according to the Soxhlet extraction method. The thermogravimetric analysis was performed in the range of 30 ° C to 900 ° C, which indicated that the decomposition occurs in three stages, in stage (a) dehydration occurs, in stage (b) the decomposition of the organic matter and in step (c) the carbonates are decomposed. Steps (b) and (c) show the potential of obtaining fuels via thermochemical processes. The kinetic analysis was developed using the isoconversional methods of Friedman, Ozawa-Flynn-Wall and Kissinger-Akahira-Sunose. The best results were obtained by applying the Friedman method, which for the conversion range of 0.05≤ α ≤0.35 determines an average activation energy of 128.738 kJ/mol, an average frequency factor of 2.37E+08 min-1, with an R2 average of 0.858. In the range of 0.45≤ α ≤0.95, there is an average activation energy of 156.584 kJ/mol, an average frequency factor of 1.81E+08 min-1 and an average R2 of 1.

Instituciones: Universidad Nacional de Ingeniería