Membrane bioreactor (MBR) technology combines the functions of a biological
reactor with membrane separation. The MBR replaces two stages of the conventional
activated sludge process (biotreatment and clarification) with a single, integrated process.
The main advantages of MBRs include reduced footprint, reduced sludge production due
to a high biomass concentration in the bioreactor, and higher quality product water.
The most substantial drawback of MBRs is membrane fouling. Fouling causes permeate
flux decline and increases the frequency of membrane cleaning and replacement.
Approximately 98% of MBR systems are aerobic MBRs. They have mostly
been used to treat domestic and industrial wastewater, where a small footprint is required,
water reuse is desired, or stringent discharge standards exist. In recent years there has
been growing attention towards the use of anaerobic MBRs (AnMBRs), due to their
advantages over aerobic systems, such as lower sludge production and reduced energy
requirements.
Despite these advantages, anaerobic MBRs are a slow-developing technology,
mainly because of fouling problems. Much progress has been made in the study of
fouling mechanisms in aerobic MBRs, but the same cannot be said for anaerobic MBRs.
Fouling in anaerobic systems is still poorly understood. Although it has been
established that struvite, bacterial cells, and colloidal matter are major membrane foulants, there is still limited information on the role of extracellular polymeric substances
(EPS) and soluble microbial products (SMP) on the fouling of anaerobic MBR
membranes.
Furthermore, a novel approach in anaerobic MBRs is represented by the
submerged configuration. At present time there is very little information about this
configuration, and specifically, only two studies (Fawehinmi et al. 2005 and Hu and
Stukey 2006) have been identified in the literature concerning submerged anaerobic
MBRs.
The main objectives of the current study are to investigate the influence of
operating conditions on the production of EPS and SMP in submerged AnMBRs and to
determine the role of these metabolic byproducts on membrane fouling. Includes 6 references, figure.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 350 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 4 |
| Published : | 03/01/2007 |
