The use of dispersed sulphided molybdenum and hydrous titanium oxide (HTO) catalysts enable tar yields in excess of 60% daf coal to be obtained for bituminous coals in fixed-bed hydropyrolysis using relatively mild conditions. However, it was found that a key difference between hydropyrolysis and ba
Effect of heating rate on normal and catalytic fixed-bed hydropyrolysis of coals
β Scribed by Baoqing Li; Stuart C. Mitchell; Colin E. Snape
- Publisher
- Elsevier Science
- Year
- 1996
- Tongue
- English
- Weight
- 536 KB
- Volume
- 75
- Category
- Article
- ISSN
- 0016-2361
No coin nor oath required. For personal study only.
β¦ Synopsis
Fixed-bed hydropyrolysis tests have been conducted on a UK bituminous coal (Gedling), the Wyodak Argonne Premium coal sample and the high-sulfur Mequinenza lignite at a pressure of 15 MPa with heating rates of 5 and 300 K min-' . The tar yields and overall conversions increased markedly by -5-20 wt% daf coal as the heating rate was decreased from 300 to 5 Kmin-' for final temperatures of 520 and 6OO"C, both with and without a sulfided molybdenum catalyst. Conversions of >90 wt% were achieved with slow heating in catalytic hydropyrolysis for all three coals. The small increases in gas yield indicated that tar-forming as opposed to hydrogasification reactions are promoted by slow heating. These results demonstrate the value of slow heating for analytical applications of hydropyrolysis, which include the determination of organic sulfur forms and the covalently bound biomarker hydrocarbons in coals and petroleum source rocks.
π SIMILAR VOLUMES
Fixed-bed hydropyrolysis has been investigated by treating 100 g coal up to 900Β°C and 10 MPa. The devolatilization rate of Beringen coal (32.8 wt% volatile matter) treated on a fixed bed approximates to that obtained by flash hydropyrolysis. However, the oil yield is smaller because of the slower he
Hydropyrolysis (HyPy) of a high-sulphur (4.3 wt% mf) and high-calcite (7.3 wt% mf) subbituminous coal (Sulcis coal) has been studied in a semi-batch fixed-bed reactor under a pressure of 1 or 3 MPa from 580 to 850Β°C. The maximum temperature attained is not necessarily the temperature that the reacto
A semi-analytical solution of the system of simultaneous second order partial differential equations appearing in the design of a chemical reactor with axial and radial profiles of temperature ?(x, z) and conversion f (x, z) is presented for the case that the rate equation may be approximated by the