The influence of pyrolysis type on shale oil generation and its composition (upper layer of Aleksinac oil shale, Serbia)

Abstract

The influence of pyrolysis type on the shale oil generation and its composition was studied. Different methods such as Rock-Eval pyrolysis, thermogravimetric analysis (TGA) and pyrolysis in the open and closed systems were applied. Samples from the Upper layer of Aleksinac oil shale (Serbia) were used as a substrate and first time characterized in detail. The impact of kerogen content and type on the shale oil generation in different pyrolysis systems was also estimated. Majority of the analysed samples have total organic carbon content > 5 wt. % and contain oil prone kerogen types I and/or II. Therefore, they can be of particular interest for the pyrolytic processing. The thermal behaviour of analysed samples obtained by TGA is in agreement with Rock-Eval parameters. The pyrolysis of oil shale in the open system gives higher yield of shale oil than the pyrolysis in the closed system. The yield of hydrocarbons (HCs) in shale oil produced by the open pyrolysis system corresponds to an excellent source rock potential, while HCs yield from the closed system indicates a very good source rock potential. The kerogen content has a greater impact on the shale oil generation than kerogen type in the open pyrolysis system, while kerogen type plays a more important role on the generation of shale oil than the kerogen content in the closed system. The composition of the obtained shale oil showed certain undesirable features, due to the relatively high contents of olefinic HCs (open system) and polar compounds (closed system), which may require further treatment to be used.

Study of pyrolysis of high density polyethylene in the open system and estimation of its capability for co-pyrolysis with lignite

“…10 On the other hand, in the open system, the secondary processes occur less, because of the relatively short residence time of the primary generated products, that are being carried by an inert gas, and then immediately collected in a cold trap. 14 Recently, the pyrolysis in the open system has been proven as a method for significant thermal degradation of the following polymeric materials: carboxymethyl cellulose, hydroxyethyl cellulose, polyacrylamide and poly(vinylpyrrolidone) as well as for the accurate detection of their primary pyrolysis products. [15][16][17] Considering that the pyrolysis of oil shale and coal in the open system prevents secondary processes, enabling higher yield of liquid products and that their co-pyrolysis with HDPE can be an attractive way to improve the conversion of these natural substrates into liquid products, as well as for the utilisation of waste HDPE, in the present paper pyrolysis of HDPE in the open system was studied in detail.…”