| 摘要 |
<p>The invention relates to a method for purifying a fluid flow, in particular waste water, from which floating dust has been removed, comprising the steps of: a) removing volatile components from the flow (2,3); b) subjecting the flow to an oxidation treatment (4); c) separating the flow into a first sub-flow containing monovalent ions and a second sub-flow containing heavy metals (5); d) removing fluorides from the first sub-flow by precipitation by means of a calcium salt (8); e) converting the monovalent ions from the first sub-flow into corresponding acids and bases (10); and f) recovering the heavy metals in metallic form from the second sub-flow (13). The different steps of the method can be performed in practice in various ways but a method is preferred wherein the volatile components are removed by a steam stripping process, the oxidation takes place by means of ozone and UV radiation, separation of the flow is performed by means of reverse electrodialysis, the fluorides are separated by precipitation with calcium chloride, the sub-flow containing the monovalent ions is separated into acids and bases by means of bipolar membrane techniques and the heavy metals are precitpitated electrolytically. The invention further relates to a system of devices for performing the method according to the invention. It is likewise possible to apply one or more of the different steps alone or in combination with a conventional waste water purification process. <IMAGE></p> |
