The content of fulvic acids in the primary effluent at the Płaszów WWTP in Kraków

Department of Environmental Engineering, Institute of Water Supply and Environmental Protection, Cracow University of Technology, 24 Warszawska, 31-155 Cracow, Poland

^* Corresponding author: dominika.lominska@pk.edu.pl

Abstract

Municipal wastewater contains significant amounts of organic substances of both natural and anthropogenic origin. Wastewater treatment removes most of contaminants, however new substances are formed as a result of biochemical changes taking part during the treatment process; some of them remain in the final effluent and may pose a threat to life and health of living organisms. Humic substances (HS), which include soluble fulvic acids (FA) are contaminants commonly found in wastewater. This is why the research attempted to examine the content of fulvic acids in mechanically treated wastewater at the Płaszów Wastewater Treatment Plant (WWTP) in Kraków. The study was conducted to assess the quantities of the pollution load coming to the plant. FA were separated (isolated) at a hydrophobic ion exchanger, and then subjected to qualitative analysis to determine their elemental composition and degree of contamination with metals and other substances. Studies were also conducted in the infrared spectrum to determine the effects of internal structure of fulvic acids. Humic acids (HA) are precursors of chloroorganic compounds and other carcinogenic, mutagenic and teratogenic substances in oxidation and disinfection processes. Therefore the problem of FA in the final effluent is important, because of their amount and location of a wastewater discharge point.