Effect of organic loading rate on the production of Polyhydroxyalkanoates from sewage sludge

Laura Isern-Cazorla; Antonio Mineo; María Eugenia Suárez-Ojeda; Giorgio Mannina

doi:10.1016/j.jenvman.2023.118272

Effect of organic loading rate on the production of Polyhydroxyalkanoates from sewage sludge

J Environ Manage. 2023 Oct 1:343:118272. doi: 10.1016/j.jenvman.2023.118272. Epub 2023 May 29.

Authors

Laura Isern-Cazorla¹, Antonio Mineo², María Eugenia Suárez-Ojeda³, Giorgio Mannina⁴

Affiliations

¹ Engineering Department, Palermo University, Viale delle Scienze ed. 8, 90128, Palermo, Italy; GENOCOV Research Group, Department of Chemical, Biological and Environmental Engineering, School of Engineering, Edifici Q, c/ de les Sitges s/n, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain.
² Engineering Department, Palermo University, Viale delle Scienze ed. 8, 90128, Palermo, Italy.
³ GENOCOV Research Group, Department of Chemical, Biological and Environmental Engineering, School of Engineering, Edifici Q, c/ de les Sitges s/n, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain.
⁴ Engineering Department, Palermo University, Viale delle Scienze ed. 8, 90128, Palermo, Italy. Electronic address: giorgio.mannina@unipa.it.

PMID: 37257232
DOI: 10.1016/j.jenvman.2023.118272

Abstract

The aim of this work was to study the effect of organic loading rate on the production of Polyhydroxyalkanoates (PHA) from sewage sludge. Synthesis of PHA using sewage sludge as platform was achieved in this work. Three pilot-scale selection-sequencing batch reactors (S-SBR) were used for obtaining a culture able to accumulate PHA following a strategy of aerobic dynamic feeding (ADF) at different volumetric organic-loading-rate (vOLR): 1.3, 1.8 and 0.8 g COD L^-1 d^-1 for S-SBR 1, S-SBR 2 and S-SBR 3, respectively. Decreasing the vOLR enhanced the general performance of the process as for organic matter removal (from 99.2% ± 0.3% in S-SBR-3 to 92 ± 2 in S-SBR-2) while the opposite trend was recorded for PHA production (6.0 PHA % w/w in S-SBR-3 vs 13.7 PHA % w/w in S-SBR-2 at the end of the feast phase). Furthermore, indirect and direct emissions, as N2O, were evaluated during the process for the first time. Finally, three accumulation tests were performed achieving 24% w/w.

Keywords: Aerobic dynamic feeding; Polyhydroxyalkanoates; Resource recovery from wastewater; Selection; Sequencing batch reactor; Sewage sludge.

MeSH terms

Bioreactors
Polyhydroxyalkanoates*
Sewage*

Substances

Sewage
Polyhydroxyalkanoates