Process for separating silicon compounds contained in a hydrochloric bath used for pickling

摘要

This process in which the used bath is recycled after concentration at (1) by elimination of water at (2), followed by a treatment for recovering iron oxides at (10), is characterized in that it comprises carrying out a tangential microfiltration at (5) of the concentrated bath so as to separate therefrom the silicon compounds in the non-ionic form and thereby concentrate them, and recirculating the major part of the fraction of this bath (11-17) containing these concentrated silicon compounds so as to promote the precipitation of the non-ionic compounds of the silicon.