Answer:hydrated lime is used initially to precipate most of the sulfate as gypsum
Explanation:
The most common method for removing sulfate from highly concentrated waste water is the addition of lime which precipitate calcium sulphate
The next step is the addition of CESR reagent to lime water treated precipitate sulfate..we have the steps as followed: initial surface precipation, metal hydroxide precipitation, final surface precipitation and pH reduction/recarbonation