Celem pracy było określenie możliwości wykorzystania reakcji pogłębionego utleniania z zastosowaniem odczynnika Fentona w procesie higienizacji wstępnie przefermentowanych osadów ściekowych oraz porównanie uzy-skanych rezultatów z techniką wykorzystującą jedynie kondycjonowanie z zastosowaniem soli Fe2+ oraz H2O2.
The most common methods of sludge management such as anaerobic or aerobic stabilization, liming do not let obtain completely safe products in the respect of sanitary effects. Biological pollutants leaching to the soil disturb biocenotic balance and are potentially hazardous for the other organisms. The composition of the sludge from municipal wastewater treatment plants is complex. The sludge consists of pathogens not only from sick or disease carrier but also from landfills, slaughterhouses and other sources such as trade, industry and agriculture. The pathogens reach wastewater treatment plants and get out during treatment process. Needed most of all are modifications and changes to the currently practiced, moreover, search and study at new, effective and cheap solutions determining environmentally hazardous substances removal. The operations should effectively improve sludge dewatering parameters, decrease mass of the sludge, remove organic substances susceptible to putrefaction and diminish the number of pathogenic and parasitic organisms. In wastewater treatment alternative methods versus commonly applied in contaminant removal make use of chemical methods mainly advanced oxidation process (AOP). One of the methods of AOP is Fenton reaction that occurs while using hydrogen peroxide (H2O2) and iron ions as a catalyst of the process. The reaction leads to catalysis break-down of hydrogen peroxide in presence of ferrous ions Fe2+, what results in free radicals generation OHo, with high oxidizing potential of 2,8 V. The aim of the study was to assess of the AOP with Fenton's reagents on sanitary effect of the sludge after preliminary anaerobic digestion from domestic wastewater treatment plants. Moreover, the results were compared with methods using merely sludge conditioning with ferrous ions and hydrogen peroxide. The investigations were conducted in three phases, on laboratory-scale experimental stands. The importance of Fenton's reagents doses, ferrous sulphate and hydrogen peroxide doses as an independent agents influencing on the technological effects were determined. Microbial analysis concentrated on coli form bacteria, faecal coli form bacteria, anaerobic endosporous form of Clostridium perfringens and microorganisms from genus of Salmonella. In activated sludge not exposing on chemical treatment, the number of coli form bacteria was approximately on the level of 6,8 ź 105 MPN/g d. m., faecal coli forms 5,6 ź 105 MPN/g d. m., however, anaerobic endosporous form of Clostridium perfringens was on the level of 1,2 ź 104 CFU/g d. m.. Microorganisms Salmonella were present. The most effective method to improve the sanitary effects of the excess sludge was advanced oxidation process (AOP). The best results revealed that the number of coliforms was reduced to 6,2 ź 101 MPN/ g d.m. and anaerobic forms to 4,9 ź 101 CFU /g d. m. Salmonella did not appear in the sludge. The efficiency of presented method depended directly on chemical reagents doses.