Assessment of the Drinking Water Quality of a Rural Distribution Network in the North of Iran by Corrosion and Scaling Indices Publisher



Mokhtari Z¹ ; Yousefzadeh S^{2, 3} ; Safari M¹ ; Brahmand MB⁴ ; Soleimani H¹ ; Yaghmaeian K¹ Show Affiliations
Source: Desalination and Water Treatment Published:2020

Abstract

Corrosion and scaling occur due to the physicochemical reactions between the inner surface of pipes, cations, and anions. These reactions lead to the entrance of heavy metals into the water and scale formation on the inner surface of pipes. The present cross-sectional study conducted in 2015–2017 aimed to investigate the drinking water quality of rural distribution networks in the north of Iran by using corrosion and scaling indices. Samples were taken from 53 points of the distribution network by random sampling and sent to the laboratory under standard conditions. The mean chemical parameters of the total dissolved solids, electrical conductivity, pH, chloride concentration, bicarbonate, and total hardness were 687.83 ± 267.69 mg/L; 1,058.21 ± 411.83 µmoh/cm; 7.32 ± 0.28; 173.04 ± 12.08 mg/L; 530.52 ± 157.39 mg/L; and 511.39 ± 153.00 mg/L, respectively. The corrosion and scaling indices, including the Larson–Skold index (LS), Ryznar stability index (RSI), Puckorius scaling index (PSI), Langelier saturation index (LSI), and aggressiveness index (AI) were also stud-ied. According to the results, the average values of LSI, RSI, PSI, LS, and AI were 0.41 (±0.59), 6.50 (±0.59), 5.32 (±0.69), 0.50 (±0.24), and 10.54 (±0.46), respectively. Moreover, according to LSI, RSI, PSI, LS, and AI indices, the scaling tendency in the water network was 98.11%, 18.87%, 79.25%, 92.45%, and 1.89%. The spatial distribution of scaling indices was determined using the geographic information system. © 2020 Desalination Publications. All rights reserved.