ARTIFICIAL COALIFICATION - COMPARISON OF CONFINED PYROLYSIS AND HYDROUS PYROLYSIS

Two artificial coalification series were obtained by pyrolysing an immature coal in hydrous and confined systems. The solid residues as well as extractable liquid hydrocarbons were analysed. Both pyrolysis systems yield similar results that are generally consistent with data from natural coalification series. However, the amounts of total soluble organic matter are greater in artificial maturation than in natural maturation. This is attributed to the ability of natural coals to retain significant quantities of hydrocarbons. Emphasis is also placed on the amount of expelled hydrocarbons obtained by hydrous pyrolysis, which exceeds that observed in confined pyrolysis and suspected in the natural system. Detailed inspection of the analytical results indicates slight differences between hydrous and confined pyrolysis that are tentatively attributed to pressure effects.