摘要 |
<p>The method involves depositing fly ash in a dust collector, and treating the fly ash with a gaseous region reducing agent in a temperature range between 600 and 700 degree centigrade, where the reducing agent contains carbon monoxide and hydrogen. Selective metal sulfates are converted into metallic form or sulfide form. Separation of residual water soluble compounds such as alkali sulfate and alkali chloride is performed by extracting water with subsequent fixed fluid separation after the treatment.</p> |