Corrosion potential of alluvial groundwaters in Velika Morava River basin

Abstract

This paper discusses the corrosion and scaling potential of shallow groundwater from two aquifers(Kljuc and Trnovce) in the Velika Morava River alluvium. Values of the most commonly used indicators, such as Langelier Saturation Index (LSI), Ryznar Stability Index, Larson-Skold Index and Aggressive Index were calculated to determine corrosion potential and stability. Additionally, the paper analyzes the psysico-chemichal parameters that impact corrosion processes. The calculated results show that Trnovce water source has more aggressive groundwater then - the Kljuc water source. Based on the calculated RSI values, 92.8% of the samples from Trnovce and 84.2% of the samples from Kljuc groundwater sources show corrosive potential. Calculated LSI shows that 82% of the groundwater samples from Trnovce and 36.8% of the samples from Kljuc have negative values, which implies corrosive properties and inability to retain existing CaCO3. The Aggressive Index indicates that 67.8% of the samples from Trnovce belong to moderately corrosive waters, unlike groundwaters from Kljuc water source, where only 26.3% of the samples show these properties. The small calculated values of LSkI Index, which are significantly below the limit of 0.8, imply that protective layer (film) cannot be formed. High water hardness are characteristic for both water sources, also as periodically elevated concentrations of dissolved oxygen, could contribute to the development of corrosion processes.