INFLUENCE OF PARTICLE SIZE, GRADE AND PYROLYSIS TEMPERATURE ON THE OIL YIELD FROM JORDANIAN OIL SHALES
J. O. JABER
S. D. PROBERT
School of Mechanical Engineering,
Cranfield University
Bedford MK 43 0AL, UK
P. T. WILLIAMS
Department of Fuel and Energy,
Leeds University
Leeds LS2 9JT, UK
| The effect of changes in some of the experimental parameters on the oil yield has
been determined in a laboratory scale reactor heated by an external electrical heater. Five categories of particle sizes
of oil shale samples from two deposits in Jordan were pyrolysed by employing a fixed bed retorting system. The reactor
and the oil shale sample were heated at a constant rate, and nitrogen gas was used to purge the sample, continuously,
in order to remove the pyrolysis products from the reactor as well as to reduce secondary reactions. The liquid products
were condensed and collected in a series of cold glass-traps and the off-gases analysed for their hydrocarbon and
non-hydrocarbon species. Subsequent experiments were carried out employing a thermogravimetric analyser using only the four smallest particle sizes under similar conditions as applied to the fixed bed retort. The activation energy was determined using the integral method. The pyrolysis of the investigated shales was found to comply with first-order kinetics within the limits of experimental error. Increasing the particle size resulted in a slight rise in the liquid oil yield, but simultaneously the total gaseous production was decreased. The highest oil yield was obtained at a temperature of 480 (±30) oC. Results obtained from this study agree with those for other grades of oil shales extracted from various deposits world-wide. |