The potential of ozonation to reduce impact of waste sludge-entrapped microplastics to biogas production

Lekše, Nina (author), Griessler Bulc, Tjaša (author), Žgajnar Gotvajn, Andreja (author)

Due to low degradability of plastic materials, high usage, and low cost, microplastics (MPs) is becoming ubiquitous environmental pollutant. Wastewater treatment plants (WWTP) are one of main sources, where most of the MPs from wastewaters ends in waste sludge. Anaerobic digestion is one of most promised techniques of waste sludge management. The aim of this paper was to evaluate the impact of polyethylene terephthalate (PET) and polypropylene (PP) microplastics in the waste sludge with and without ozonation as possible pretreatment, on biogas and methane production with OxiTop$^®$ method. In the first set of experiments, PET inhibited (up to 6% at 0.1 g $L^{−1}$) or promoted (up to 3% at 1 g $L^{−1}$) methane production but increased cumulative biogas production (up to 38% at 0.5 g $L^{−1}$). PP inhibited methane production (up to 5% at 0.5 g $L^{−1}$) but its impact on biogas production was dependent upon concentration of MPs added. In the second set of experiments, pretreatment of non-contaminated waste sludge by ozonation (3.54 $g_{ozone}$ $h^{−1}$) inhibited methane yield. Longer time of ozonation of PP-contaminated waste sludge reduced inhibition of methane yield, while in the case of PET-contaminated waste sludge, it was increased.

• Language: English
• Keywords: biogas production, methane yield, ozonation, polyethylene terephthalate, polypropylene, waste sludge
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FKKT - Faculty of Chemistry and Chemical Technology; ZF - Faculty of Health Sciences
• Publication status: Published
• Publication version: Version of Record
• Year: 2024
• Number of pages: Str. 255–266
• Numbering: Vol. 46, no. 3
• PID: 20.500.12556/RUL-155486
• UDC: 66.094.3-926.214
• ISSN on article: 0191-9512
• DOI: 10.1080/01919512.2024.2332286
• COBISS.SI-ID: 191347203
• Publication date in RUL: 04.04.2024

Record is a part of a journal

• Title: Ozone: science & engineering
• Shortened title: Ozone: sci. eng.
• Publisher: Taylor & Francis, International Ozone Association
• ISSN: 0191-9512
• COBISS.SI-ID: 2223382

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: proizvodnja bioplina, donos metana, ozonacija, polietilenteraftalat, polipropilen, odpadno blato