AUTHOR(S) / AUTOR(I): Dragana Žmukić 
, Đurđa Kerkez , Nataša Duduković , Dragan Kovačević , Anita Leovac Maćerak
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DOI: https://doi.org/10.46793/SBT26.777Z
ABSTRACT / SAŽETAK:
Sludge from wastewater treatment plants as an organic substrate rich in nutrients has great potential for use in agriculture. Given the potential risks of contamination with bacteria, pathogens, heavy metals, preliminary sludge treatment is necessary. Anaerobic digestion of sludge is an environmentally acceptable and energy-efficient method especially if further use of sludge in agriculture is planned, in order to further improve it, additional pretreatments are required. In our study, we used acetic acid as a pretreatment. Acetic acid has been shown to be effective in promoting biogas production. The produced digestate showed an increase in carbon content with in increase in the dose of acetic acid, which is considered suitable for plant growth. The lowest C/N ratio was 5.82 in the sample with highest dose of acetic acid. Analyzed sludge is rich in nutrients; the phosphours concentration is 50 mg/L, while magnesium is 11.4 mg/L. Heavy metal concentrations are low, which reduces the risk from contaminations. All of the above points to the convinience of applying sludge to agricultural lands, which would strengthen the agricultural sector and replace the use commercial artificial fertilizers.
KEYWORDS / KLJUČNE REČI:
sludge, anaerobic digestion, sustainable, fertilizers, agriculture
ACKNOWLEDGEMENT / PROJEKAT:
The authors greatefully acknowledge the financial support of te Ministry of Science, Technological Development and Innovation of the Republic of Serbia (Grants No. 451-03-33/2026-03/200125 & 451-03-34/2026-03/200125.
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