Enhanced membrane fouling control through self‐forming dynamic membrane and sponge‐wrapped membrane: A novel membrane bioreactor

Abstract

Membrane technology offers a wide variety of advantages in wastewater treatment, but fouling impedes its widespread applications. Hence, in this study, a novel method was tried to control membrane fouling by combining the self‐forming dynamic membrane (SFDM) with a sponge‐wrapped membrane bioreactor. The configuration is termed a “Novel‐membrane bioreactor” (Novel‐MBR). To compare the performance of Novel‐MBR, a conventional membrane bioreactor (CMBR) was operated under similar operating conditions. CMBR and Novel‐MBR were run consequently for 60 and 150 days, respectively. The Novel‐MBR was composed of SFDMs in two compartments before a sponge‐wrapped membrane in the membrane compartment. In Novel‐MBR, the formation times for SFDMs on coarse (125 μm) and fine (37 μm) pore cloth filers were 43 and 13 min, respectively. The CMBR experienced more frequent fouling; the maximum fouling rate was 5.83 kPa/day. In CMBR, the membrane fouling due to cake layer resistance (6.92 × 1012 m−1) was high, and that alone contributed to 84% of fouling. In Novel‐MBR, the fouling rate was 0.0266 kPa/day, and the cake layer resistance was 0.329 × 1012 m−1. Also, the Novel‐MBR experienced 21 times less reversible fouling and 36 times less irreversible fouling resistance than the CMBR. In Novel‐MBR, the formed SFDM and the sponge wrapped on the membrane helped to reduce both reversible and irreversible fouling. With the modification tried in the present study, the Novel‐MBR experienced less fouling, and the maximum transmembrane pressure at the end of 150 days of operation was 4 kPa. Practitioner Points CMBR experienced frequent fouling, and the maximum fouling rate was 5.83 kPa/day. Cake layer resistance was dominant in CMBR and contributed to 84% of fouling. The fouling rate of Novel‐MBR at the end of the operation was 0.0266 kPa/day. Novel‐MBR is expected to perform for ≈3380 days to reach the maximum TMP of 35 kPa.