Working up process liquids in a hot galvanizing installation comprises feeding the diluate from an electrodialysis unit through a re-conditioning device to remove zinc, feeding the regenerate back to the electrodialysis unit

摘要

Working up process liquids in a hot galvanizing installation containing a bath with a Fe/Zn mixed pickling solution comprises feeding the diluate from an electrodialysis unit (18) in a regeneration phase through a re-conditioning device (16) to remove zinc; feeding the regenerate back to the electrodialysis unit; and concentrating to a value product having a high zinc content. Preferred Features: The re-conditioning device is an ion exchanger. The concentrate in the regeneration phase is concentrated to a zinc content of more than 200 g/l.