Origin of Aluminium in the Raw Drinking Water of Sofia City, Bulgaria
- PDF / 2,030,580 Bytes
- 10 Pages / 547.087 x 737.008 pts Page_size
- 107 Downloads / 164 Views
Origin of Aluminium in the Raw Drinking Water of Sofia City, Bulgaria Irina Angelova & Ivaylo Ivanov & Tony Venelinov
Received: 1 June 2020 / Accepted: 13 August 2020 # Springer Nature Switzerland AG 2020
Abstract In recent years, the concentration of aluminium in the Iskar River occasionally exceeds the environmental quality standard (EQS). The river and the Iskar Dam, build on the river, are the main drinking water source of Sofia city (Bulgaria), with population exceeding 1.2 million. The average concentrations of aluminium in the raw water entering the drinking water treatment plants of Sofia city—Bistritza and Pancharevo—in 2018 were 0.148 mg/L and 0.199 mg/L, respectively, which are very close to the limits set in Directive 98/83/ EC. This study uses multifactorial analysis, taking into account the influence of the mineral and chemical composition of sediments of the Iskar Dam, the geological conditions at the dam’s catchment area, the relationship between the aluminium concentrations and precipitation in the region and also the relationship between the aluminium concentration and the turbidity at the inlet of the Electronic supplementary material The online version of this article (https://doi.org/10.1007/s11270-020-04819-0) contains supplementary material, which is available to authorized users. I. Angelova : T. Venelinov (*) Faculty of Hydraulic Engineering, Department of Water, Sewerage, Water and Wastewater Treatment, University of Architecture, Civil Engineering and Geodesy, 1 Hr. Smirnenski Blvd, 1164 Sofia, Bulgaria e-mail: [email protected] e-mail: [email protected] I. Ivanov Faculty of Transportation Engineering, Department of Geotechnics, University of Architecture, Civil Engineering and Geodesy, 1 Hr. Smirnenski Blvd, 1164 Sofia, Bulgaria
two treatment plants, to determine the origin of aluminium in the raw drinking water of Sofia city. The obtained linear regression models for the aluminium concentration and the turbidity at the inlet are significant (p ≤ 0.001) with coefficients of determination (R2) for DWTP–Bistritza and DWTP–Pancharevo of 0.54 and 0.51, respectively. Keywords Aluminium . Drinking water . Turbidity . DWTP
1 Introduction Aluminium accounts for about 8.8% of all atoms and ranks third after oxygen and silicon spread in the earth’s crust. Aluminium is found in the air, water and plants (Kabata-Pendias and Pendias 2000) and is present in over 270 Al-containing minerals (orthoclase (K2O.Al2O3.6SiO2), anorthite (CaO.Al2O3.2SiO2), albite (Na2O.Al2O3.6SiO2), sillimanite (Al2O3.SiO2), nepheline, etc.) and clays (kaolinite (Al2O 3.2SiO2.2H2O), montmorillonite, illite, etc.) (Krewski et al. 2007). Potential sources of aluminium found in surface water include rainfall and snowmelt, dust originated from rocks and soil erosion, and human activity. In erosion processes, Al is extracted and becomes an integral part of the soil. Soil acidity, caused by nitrogen oxides and sulphur compounds, is the main reason for the release of aluminium ions and their transfer into surface water an
Data Loading...
