Porous shell quorum quenching balls for enhanced anti-biofouling efficacy and media durability in membrane bioreactors

[Display omitted] •Mobile porous balls containing active QQ media were developed for biofouling control.•QQ balls were superior in anti-fouling efficacy and stability to other media types.•QQ balls, unlike other types, maintained their high activity during long-term use.•QQ balls minimized the filtration energy at minimal aeration.•QQ balls are promising bio-media for sustainable MBR applications. Microbial quorum quenching (QQ) has been recognized as an effective anti-biofouling strategy for membrane bioreactors (MBRs), but long-term hydrogel QQ media durability is uncertain. In this study, we propose a new media design to enhance anti-biofouling efficacy and mechanical media stability. Mobile porous hard-shell balls to hold QQ sheets (named QQ balls) were found to be superior in QQ stability to both fixed and freely moving QQ sheets. Fouling mitigation by QQ balls was significant even at the lowest aeration intensity tested (51 s−1), in contrast to other QQ media. QQ balls saved substantive energy (~50%) at similar or lower fouling rates (2.8–3.2 kPa/d) compared to the others tested at the higher aeration intensity (72 s−1). QQ balls maintained their initial high level of QQ activity (~3.0 h−1) during long-term use (greater than160 d), whereas other types of QQ media did not (