1. A groundwater contains the following constituents: CO2 = 9.6 mg/L Ca2+ = 95.2 mg/L Mg2+ = 25.8 mg/L HCO3 = 198 mg/L as CaCO3 The facility is to treat 50 x 10° L/d of water from this source using lime-soda ash to reduce the hardness. Determine the quicklime and soda ash dosages for softening to stoichiometric limits. Assume the lime is 90% CaO by weight and the soda ash is pure sodium carbonate.

1. A groundwater contains the following constituents: CO2 = 9.6 mg/L Ca2+ = 95.2 mg/L Mg2+ = 25.8 mg/L HCO3 = 198 mg/L as CaCO3 The facility is to treat 50 x 10° L/d of water from this source using lime-soda ash to reduce the hardness. Determine the quicklime and soda ash dosages for softening to stoichiometric limits. Assume the lime is 90% CaO by weight and the soda ash is pure sodium carbonate.

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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