... Ferrous sulfate is a kind of common industrial raw materials, nonpoisonous and harmless, widely as sewage treatment reagent, biological fertilizer ... Second, the product specification product standards: GB10531-89 ferrous sulfate FeSO4 (7H2O - 90%, titanium dioxide content of ... original technology, low price, as the flocculant, ferrous sulfate could replace polyaluminium, alkali, polyblend of iron and ...