| 摘要 |
<p>A process for separating off chloride from a sulphide-containing alkaline liquor which is obtained in association with the production of chemical pulp. According to the invention, the liquor is contacted, in a first gas/liquid contact zone, by a carbon dioxide-containing gas, the carbon dioxide partial pressure of which exceeds 0.2 atm, in order to obtain an alkaline liquid which contains dissolved alkali hydrogen carbonate and chloride compounds and which is drawn off and transferred to a second gas/liquid contact zone, in which a lower pressure is maintained than in the first gas/liquid contact zone, in order to obtain an alkaline liquid which contains alkali carbonate and chloride compounds, and hydrogen sulphide which is driven off. From the second gas/liquid contact zone are drawn off, firstly, alkaline liquid containing alkali carbonate and chloride compounds, which is transferred to the first gas/liquid contact zone, and, secondly, alkaline, and in the main sulphide-free, liquid which contains alkali carbonate and chloride compounds and which is transferred to a system for separating off chloride compounds.</p> |
