| 摘要 |
<p>There are many occasions when, as the result of some industrial process, there is produced an oil-in-water emulsion with metal ions dissolved in the water. This cannot be disposed of as it is - and in any case some of the 'contaminant' materials are valuable, and worth recovering. Current methods used for this all have several serious drawbacks - they are costly in time and space, have very minimal recycling benefits, and end up producing similar amounts of toxicity (albeit in a different form) to those that existed before treatment began. They also, and without exception, achieve an incomplete separation, leaving each separated fraction contaminated to some degree by the others. The present invention proposes a novel separation method relatively free from these problems. It is one wherein, following a conventional continuous centrifugation, which mechanically separates the feedstock waste stream into disposable floating oil, disposable settled solids, and 'dirty water', that 'dirty water', which is basically on oil-in-water emulsion with minerals dissolved in the water, is further treated by a cascade-like acidification stage, both to 'break' the emulsion and to precipitate most of the minerals, first by dissolving therein CO2 (using a diffuser) to start the two processes off, and then by mineral acid acidification to complete the two processes, whereafter the 'mixture' is again centrifuged, and the oil, water and solids components are again mechanically separated off.</p> |
