It is widely recognised by MBR practitioners that membrane bioreactors, and specifically those treating municipal wastewater, are subject to what is sometimes referred to as ‘ragging’. When the membrane module is removed, characteristic thick strands of material can be seen hanging from the bottom of the module.
In October 2009, we received a list of what was thought to be the 20 largest MBRs in the world at that time. The peak daily flow capacities on that list ranged from 30 to 100 MLD, with the total capacity being just over 1,000 MLD. 16 of the top 20 installations were fitted with GE’s Zeeweed technology, though the largest – Origin Water’s Wenyu river plant in Beijing – was based on Asahi Kasei membranes.
Membrane bioreactor (MBR) systems are becoming more accepted in the wastewater industry as an alternative to traditional conventional treatment systems. A number of factors have been instrumental in the acceptance of the MBR technology. Victoria Kippax explains the MemPulse MBR system.
Membrane bioreactors (MBRs) are growing both in size and number, reflecting a growing confidence in the technology. The number of MBR membrane module products is currently increasing by 3−5 a year, and the market itself is growing exponentially at a rate between 11.5 and 13%. Whereas in the past MBRs may have been disregarded in favour of conventional treatment plants, ...
Fouling in MBRs arises when materials either form a layer on the surface of the membrane or plug its pores. Studies are, however, generally unable to distinguish between coating of the membrane surface and phenomena relating to the agglomeration of solids. The latter has received little or no attention from the scientific community, and yet such irreversible deposition of solids clearly impairs MBR operation.