جستجوی مقالات مرتبط با کلیدواژه « corrosion indices » در نشریات گروه « پزشکی »

Background and In the area of water quality issues, much attention has been paid to water corrosivity and scaling potential since the water tendency to each of them can impose huge financial losses and many health problems. In this descriptive cross-sectional study, 38 water samples were collected from 19 sampling sites including wells and aqueducts of Sarayan, Iran, in spring and autumn seasons of 2015, and analyzed for total dissolved solids, calcium hardness, total alkalinity, water temperature, pH, Langelier Saturation Index, Ryznar Stability Index, Aggressive Index, and Puckorius Index. The results were analyzed by Excel and water stability analyzer Software and were compared with standard limits. It was found that TDS, temperature, pH, alkalinity, and hardness of water were lower than the maximum allowed limits, but calcium hardness was also lower than the optimum value for drinking water. The average value of LSI, RSI, AI, and PI in spring was 0.437±0.264, 7.25±0.368, 12.33±0.273, and 7.37±0.432, while the average values of these indices in autumn were 0.501±0.229, 7.231±0.359, 12.55±0.225, and 7.33±0.503, respectively. According to corrosion indices, drinking water of Sarayan County was relative scaling. Considering the negative effects of scale-forming water on pipe diameter, and flow rate and probable economic damages, control measures must be taken to prevent scaling in water resources

Background & Aims of the Study: Corrosion and scaling play undesirable effects on transmission and distribution system of drinking water. The aim of this study was to assess the corrosion and scaling potential of drinking water resources in Babol city, Iran.
Totally, 54 water samples were collected from 27 wells in spring and autumn. Calcium hardness, pH, total alkalinity, total dissolved solids, and temperature were measured, using standard methods. The Langelier, Rayzner, Puckhorius, Larson and aggressive indices were calculated and data were analyzed by SPSS 19. To compare the mean values of each index, the results were analyzed using t-test.
The range of temperature, pH, TDS, total alkalinity and calcium hardness were 16-24°c; 6.8-7.89; 445-1331 mg/l; 322.9-396 mg/l and 250.50-490 mg/l, respectively. The mean of Langelier and Ryznar indices in drinking water samples in spring and autumn was 0.14, 0.15; 7.28 and 7.35, respectively. The mean of Puckhorius and Larson indices in these seasons was 11.9, 11.95 and 0.95 and 0.93, respectively. The mean of aggressive index was 6.17 and 6.27, respectively. Overall, 82.2%, 100%, 94.6%, 100% and 85.7% of water samples were corrosive based on the Langelier, Ryznar, Puckhorius, Larson and aggressive indices, respectively.
According to these results, drinking water of Babol city has corrosion potential. Therefore, the water quality should be controlled based on pH, alkalinity and hardness parameters, along with the use of corrosion resisting materials and pipes in drinking water distribution systems.

This paper discusses the corrosion and scaling potential of Tabriz drinking water distribution system in Northwest of Iran. Internal corrosion of piping is a serious problem in drinking water industry. Corrosive water can cause intrusion of heavy metals especially lead in to water, therefore effecting public health. The aim of this study was to determine corrosion and scaling potential in potable water distribution system of Tabriz during the spring and summer in 2011. This study was carried out using Langlier Saturation Index, Ryznar Stability Index,Puckorius Scaling Index, and Aggressiveness indices. Eighty samples were taken from all over the city within two seasons, spring, and summer. Related parameters including temperature, pH, total dissolved solids, calcium hardness, and total alkalinity in all samples were measured in laboratory according to standard method manual. For the statistical analysis of the results, SPSS software (version 11.5) was used The mean and standard deviation values of Langlier, Ryznar, Puckorius and Aggressiveness Indices were equal to -0.68 (±0.43), 8.43 (±0.55), 7.86 (±0.36) and 11.23 (±0.43),respectively. By survey of corrosion indices, it was found that Tabriz drinking water is corrosive. In order to corrosion control, it is suggested that laboratorial study with regard to the distribution system condition be carried out to adjust effective parameters such as pH.