Combining submerged membrane technology with anaerobic and ...

Chapter 4support were added in this chamber. Finally, the membrane filtration was carried out in a20 L aerobic chamber, where a membrane module Zenon ZW10 with a surface area of 0.9m 2 was employed. This module consisted of PVDF hollow-fibre membrane, with a poresize of 0.04 µm. The membrane was operated in cycles of 7.5 min with a permeationperiod of 7 min and a backwashing period of 0.5 min. The membrane filtration chamberwas aerated in order to minimize membrane fouling. The specific air demand (SAD m)applied was 0.7 Nm 3·m -2·h -1 . An internal recirculation between membrane filtration andbiofilm aerobic chambers was implemented in the MBR (R=1). The operation of the systemwas controlled by a PLC (Siemens S7-200) connected to a computer. Trans-membranepressure (TMP) data was measured with an analogue pressure sensor (Efector500 PN-2009) and collected in the PC via an analogue PLC module Siemens EM 235.The UASB reactor was seeded with 50 L of anaerobic biomass (27 g·L -1 ) from theinternal circulation anaerobic reactor of a brewery industry located in Galicia (Spain),whereas 5 L of biomass from a MBR pilot plant treating urban wastewater was employedas an aerobic biomass inoculum.Figure 4.1. Schematic diagram of the system. (1) UASB reactor, (2) Biofilm aerobicchamber, (3) Membrane chamber, (4) Feeding and recirculation, (5) Permeate(backwashing), (6) Biogas. P1, P2, P3, P4 and P5 refer to the sampling ports.112