Experimental Study of Low-Temperature Shale Combustion and Pyrolysis Under Inert and Noninert Environments

Abstract

Summary In this study, shale samples were heated under inert and noninert environments to increase the permeability of the shale. The nanoscale pore structure changes under combustion and pyrolysis [air, nitrogen (N2), carbon dioxide (CO2), and argon (Ar)] conditions were investigated. It was found that pore diameters increased under all the gas environments. Pore diameters increased more significantly under air environment compared with other gas conditions. However, the diameters of the shale particles remained almost constant during combustion. Moreover, gases emitted from the shale during the combustion and pyrolysis process were investigated using thermogravimetric analysis coupled to Fourier-transform infrared spectroscopy (TGA-FTIR). Finally, scanning electron microscopy (SEM) images showed larger pores on the surfaces of the combusted and pyrolyzed shale samples.