A drinking water treatment plant is to treat 50 x 10° L/day of water from the source in Question 1 using excess lime-soda ash process to reduce the hardness. Assuming (a) the final Ca²+ and Mg2+ hardness in the water is 30 and 10 mg/L as CaCO3, respectively, (b) 62.5 mg/L as CaCO3 excess lime is to be used, and (c) 10 mg/L as CaCO3 of Mg(OH)2 and 15 mg/L of CaCO3 are to be converted to HCO3 by second stage re-carbonation to reach water stability.

A drinking water treatment plant is to treat 50 x 10° L/day of water from the source in Question 1 using excess lime-soda ash process to reduce the hardness. Assuming (a) the final Ca²+ and Mg2+ hardness in the water is 30 and 10 mg/L as CaCO3, respectively, (b) 62.5 mg/L as CaCO3 excess lime is to be used, and (c) 10 mg/L as CaCO3 of Mg(OH)2 and 15 mg/L of CaCO3 are to be converted to HCO3 by second stage re-carbonation to reach water stability.

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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