my suggestion is to separate ...
Published by MARCO VALLERO
my suggestion is to separate as much as possible suspended solids before coagulation and flocculation proces then use calcium hydroxide to rise the ph to 9-9,5, alumium sulphate as coagulant and anionic polielecrtolite as flocculant.
we have experieced succesfully this proces in a tannery that produce hides treated with tannins.
regards
Marco Vallero