| 摘要 |
A method of processing waste iron chloride solution comprising ferrous chloride, ferric chloride or possible mixtures thereof, and optionally free hydrochloric acid is disclosed, said method comprising the following steps: a concentration step, wherein said waste iron chloride solution is concentrated to a concentrated liquid having an iron chloride concentration of at least 30% by weight, preferably at least 40% by weight; optionally an oxidation step, wherein ferrous chloride contained in the concentrated liquid obtained from said concentration step is oxidized to ferric chloride to obtain a liquid containing ferric chloride; an hydrolysis step, wherein the liquid containing ferric chloride optionally obtained from said oxidation step is hydrolyzed at a temperature of 155 - 350 °C while maintaining the ferric chloride concentration at a level of at least 65% by weight, to generate steam containing hydrogen chloride and liquid containing ferric oxide; a separation step, wherein ferric oxide is separated from said liquid containing ferric oxide obtained in said hydrolysis step and a recovery step, wherein steam containing hydrogen chloride obtained in said hydrolysis step is condensed to recover hydrochloric acid at a concentration of at least 10% by weight, preferably at least 15% by weight, wherein the condensation energy of the hydrogen chloride containing steam obtained in the recovery step is directly or indirectly used as a heating source for the said concentration step which concentration step is performed under reduced pressure.
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