2. A dose of 41 mg/L of alum is used in coagulating a turbid water at a water treatment plant treating a flow rate of 32 million gallons per day (mgd). The natural alkalinity of the source water is 10 mg/L (as CaCO3). A l_{2}\left(S O_{4}\right)_{3} 14 H_{2} O+6 H C O_{3}^{-} \longrightarrow 2 A l(O H)_{3 \downarrow}+3 S O_{4}^{2-}+14 H_{2} O+6 C O_{2} a) Will the alkalinity be completely consumed in the reaction? If not, then how much alkalinity will be left? If so, then what concentration of caustic soda (NaOH) must be added to avoid a change in the pH? b) How many kg of aluminum hydroxide (Al(OH)3) is produced per day?

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