Evaluation of a novel physical cleaning strategy based on HF membrane rotation during the backwashing/relaxation phases for anaerobic submerged MBR
Author
Vera Peña, Luisa MaríaDate
2017Abstract
A novel physical cleaning strategy based on membrane rotation was investigated in an anaerobic membrane
bioreactor treating wastewater. This strategy was proposed to improve the fouling removal effectiveness of the
traditional physical cleaning techniques (such as backwashing and relaxation) by the shear-enhanced conditions
associated with the rotation. The effectiveness of this strategy has been investigated in a bench filtration unit
during short-term tests and also compared to the conventional mode with gas scouring. Based on the
resistances-in-series approach, the external residual fouling has been identified as the main factor determining
the process productivity. The contribution of this type of fouling obtained with the rotating membrane was
lower than with the gas scouring application (56–18% versus 60–53%, respectively). Other operational
parameters such as the transmembrane pressure set-point for cleaning initiation and the backwashing time
have also showed a significant influence on external fouling re-dispersion. A long-term test revealed the
sustainability of the operation during more than 400 h, achieving a stable net permeate flux of 6.7 L/h m 2 when
the rotating speed was fixed in 340 rpm.