Hydrogenating extraction of coal
The aim of this project was to develop a process to recover liquid fuels or chemical feedstocks by continuous extraction of coals with supercritical water vapour. One of the most important objectives was to develop a lock-hopper system for 320 bar and 450 C capable of feeding and discharging coarse solids into pressurized spaces and thus to be able to advance into pressure and temperature ranges which are typical for continuously operating thermal coal conversion plants. In parallel with development work on the lock-hopper system batchwise tests were carried out to investigate the behaviour of various coals under extraction conditions. These showed that the yield of extracted bitumen-like products is in excess of the content of volatiles according to the German norm DIN 51 720 although in each case the extraction residues still contained volatile matter. Although it was not possible to run continuous long-time tests, exploratory tests using extraction residues were performed. These showed that the same design concept can be applied without difficulty to the discharge of extraction residue from soft brown coal employed as feed. Difficulties were encountered in discharging extraction residues from bituminous or black coal and hard brown coal.
Bibliographic Reference: EUR 12215 EN (1989) FS, 30 pp., ECU 5
ISBN: ISBN 92-825-9942-6;CD-NA-
Record Number: 198910890 / Last updated on: 1994-12-01
Original language: en
Available languages: en