Inhibiting effect of quorum quenching on biomass accumulation: A clogging control strategy in gas biofilters

Controlling excessive biomass is essential for maintaining the long-term stable operation of gas biofilters. Current methods based on physical and chemical technologies can reduce removal efficiency. In this study, we developed a new method using enzymatic-quorum quenching (QQ) to simultaneously control biomass and maintain a stable removal efficiency. A 70-d biofilter operation showed that clogging was controlled with the application of enzymatic-QQ, thereby maintaining a stable operation performance. The pressure drop of the biofilter with QQ enzyme (QQBF) was 75 Pam(- 1), while that of the control biofilter (BF) was 156 Pam(- 1). Moreover, the biomass accumulation of QQBF was only 130.58 kg m(-3), while that of BF was 218.50 kg m(-3). Further analysis indicated that enzymatic-QQ decreased biofilm adhesion strength. Accordingly, the biofilm inside the QQBF detached more easily from the filler surface than that in the BF. The 16S rDNA gene sequencing results suggested that the enzymatic-QQ regulated the related functional genes, thereby changing the biofilm characteristics. Moreover, the reduced biofilm thickness and lower inactivated microbes in QQBF enhanced the metabolic activity. Overall, our results demonstrated that QQ is a promising technology for regulating biofilm characteristics and controlling the clogging of gas biofilters.