Thermogenic gases generated from coals and shales of the Upper Silesian and Lublin basins : hydrous pyrolysis approach

In order to provide a better characterization of the origin and volume of thermogenic gas generation hydrous pyrolysis (HP) experiments were performed on coals and shales at 330 and 360oC for 72 hours. The maturity range of coals and shales used for HP varies from 0.57 to 0.92% Ro. The maturity increase caused by HP at 330 and 360oC ranges from 1.32 to 1.39% and from 1.71 to 1.83%, respectively. δ13C of CH4, 2H6, C3H6 and n-C4H10 in HP gases versus their reciprocal C-number have a concave relationship, and therefore do not follow a linear trend. δ2H of CH4, 2H6 and C3H6 in HP gases versus their reciprocal H-number show both linear and convex-concave relationships. The growth of CO2 yields during HP was higher for shales than for coals. H2S yields from shales are higher than from coals, which can be connected with catalytic and adsorbed influence of shale matrix. H2 was also generated in notable quantities from water and organic matter of coals and bigger amounts from shales. N2 yields grow with the increase of Ro after 3oC HP and it is more enriched in 15N isotope than after 330C.