Silica removal in Industrial waste water

A commercial supplier of electrocoagulation plant for removal of silica in industrial waste water. Level of Si02 is ~610 mg/L. The oil and grease levels are ~ 2,000mg/L .  It is intended to reduce this substantially with Direct Aeration Flotation (DAF) and skimming off the top system. I assume the electrocoagulation would be post the DAF system? You suggestions please