Badania osadów z wodomierzy Miejskiego Przedsiębiorstwa Wodociągów i Kanalizacji w Krakowie

Abstract

In the frame of cooperation with the Municipal Water Supply and Sewage in Krakow the preliminary studies of sediments from water meters of Krakow water supply system were performed. Sediments deposited on the measuring devices installed in the water supply system, are a major technological problem and the need to replace faulty water meters is a measurable economic problem for water utilities. Chemical and phase composition investigations were carried out using proton-induced X-ray emission, energy dispersive spectroscopy, X-ray diffraction and Fourier transform infrared spectroscopy. Additionally, basing on Mössbauer spectroscopy magnetic phases were analyzed. The morphology of the chosen samples was observed on scanning electron microscopy. Mentioned methods revealed presence of amorphous and finely crystalline phases with fractions several times larger than identified crystalline one. In the crystalline phase the most frequently appeared: goethite α-FeOOH, lepidocrocite ɤ-FeOOH, and in smaller amounts: maghemite ɤ-Fe2O3, calcium carbonate CaCO3 and quartz SiO2 as well non-stoichiometric iron sulfides. In many samples nanocrystalline phase was found which due to comparative analysis, was identified as an iron hydroxide ferrihydrite with formula similar to Fe5HO8 4H2O. Moreover, presence of hematite α-Fe2O3 and akaganeite β-FeOOH phases was revealed. In several samples appearance of organic compounds were proven.