Abstract

The biofilm thickness in membrane biofilm reactors (MBfRs) is an important factor affecting system performance because excessive biofilm formation on the membrane surface inhibits gas diffusion to the interior of the biofilm, resulting in a significant reduction in the performance of contaminant removal. This study provides innovative insights into the control of biofilm thickness in O2 -based MBfRs by using the quorum quenching (QQ) method. The study was carried out in MBfRs operated at different gas pressures and hydraulic retention times (HRTs) using QQ beads containing Rhodococcus sp. BH4 at different amounts. The highest performance was observed inreactors operated with 0.21 ml QQ bead/cm2 membrane surface area, 12 HRTs and 1.40 atm. Overthis period, the performance increase in chemical oxygen demand (COD) removal was 25%, while the biofilm thickness on the membrane surface was determined to be250 μm. Moreover, acetate and equivalent oxygen flux results reached 6080 and 10 640 mg·m-2 ·d-1 maximum values, respectively. The extracellular polymeric substances of the biofilm decreased significantly with the increase of gas pressure and QQ beads amount. Polymerase chain reaction denaturing gradient gel electrophoresis results showed that the microbial community in the MBfR system changed depending on operating conditions and bead amount. The results showed that the QQ method was an effective method to control the biofilm thickness in MBfR and provideinsights for future research.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call