New concepts for submerged membrane modules in water treatment

Submerged membrane modules either in flat or hollow fibre configuration have established themselves as a standard module for membrane bioreactors (MBRs) in municipal and industrial wastewater treatment.
In recent years two new concepts using submerged membrane modules have been developed for (1) direct membrane filtration (DMF) for municipal wastewater treatment and for (2) storm and rain harvesting. The key difference between the established MBR concept and the new concepts is that the biological treatment step is excluded. In this presentation the latest development and experiences with these two new concepts will be presented.
The DMF concept operates abiotic and is an interesting alternative for municipal wastewater treatment. In this concept municipal wastewater is physico-chemically pretreated in terms of coagulation, flocculation and microsieving prior to the membrane treatment. Since the DMF concept has a high carbon rejection biogas production can be significantly increased resulting in a potential energy neutral or positive wastewater treatment process. Furthermore, the process has a smaller footprint compared to conventional wastewater treatment technologies. The potential of this application will be demonstrated based on three pilot installations in Sweden and Norway.
The water harvesting concept upgrades storm- and rainwater collected from e.g., stormwater ponds, house roof or parking lots to a quality suitable to reuse the water for none-drinking purposes such toilet flushing and garden watering. In this case, the water is pre-screened and then polished with submerged membrane modules to remove micropollutants and microplastics. Results from a pilot installation in Sweden connected to a stormwater pond will show the capacity of this concept.
Overall, it will be shown that the submerged membrane module concept has an application potential beyond MBRs.