| 摘要 |
<p>Continuous retort pyrolysis of oil shale, in which the residual shale contg. alkaline minerals, coke and sulphur cpds. is passed with an oxygen-contg. gas stream to a combustion zone. At least part of the coke is burnt, and the amt. and temp. of the gas supply are controlled to cause reaction of the gaseous S cpds. formed (e.g. SO2) with the alkaline minerals, and give an oxygen-contg. exhaust gas substantially free from S cpds. Pref. almost all the coke is burnt, with combustion zone temp. of 482-910 degrees (760-871 degrees)C. Total gaseous S cpds. in the exhaust gas are below 100 ppm., with 5 SCF max. per tonne shale, and H2S content is below 5ppm. Passage of shale residue and gas through the combustion zone in the same direction gives better control of temp. and reduces pressure drop due to collection of fine material. Max. heat energy is recovered by combustion of virtually all the coke, for use in the process or conversion into energy. Prod. gas from the shale pyrolysis is partly heated and re-circulated as heating medium, but not consumed for heating purposes.</p> |
