Membrane biology

The increased demands on the effluent quality of waste water treatment plants require new approaches and best practices and techniques. In addition to the cleaning performance of the procedure, costs are an extremely important factor in this case. This can be minimized, for example, through consistent, continued use, or integration of existing structures and plant technology. Against this background, membrane biologies were developed as a novel concept for the use of filtration membranes for municipal and industrial waste water treatment.

Through the filtration membranes immersed in the aeration tank, a biomass concentration can be achieved, which is much higher than with conventional systems with secondary sedimentation tanks. The sterile permeate without solids extracted over the membranes has industrial water quality.

Membrane systems had already been used very successfully for biomass separation for some time. These generally deal with the energy and cost-intensive cross-flow principle. In the new membrane systems these are submerged membranes, which are characterized by significantly lower energy requirements and therefore lower costs.

Through the higher possible biomass concentrations with the membrane separation process, the spatial performance of biological systems increased significantly and the reaction volume can be saved. With the appropriate choice of membrane separation limit, the waste water and substrate dwell time can be decoupled, by which also poorly biodegradable waste water substances can be eliminated.

The filtration and disinfection procedures are replaced by membrane filtration, since the permeate is sterilised and has industrial water quality.

Process flow diagram of a conventional treatment plant

Process flow diagram with membrane biology

Demonstration plant membrane biology

The membrane biology pilot plant is designed to be very flexible and mobile for the purification of municipal and industrial waste water. It consists of two standard 20’ containers, which were converted into an office/machinery container and an “open-top” wet container. The machine container includes pumps, blowers, membrane rinsing technology, instrumentation and control cabinets, and a PC with the process control system and remote data transfer for remote control. The wet container serves as an aeration tank with different size Bio-P, nitrification and denitrification zones. It contains the pressure and jet ventilation. The submerged membrane modules are in separate membrane tanks. The demonstration plant is characterised by high flexibility and quick setup and is available with all the necessary components and spare parts for the conducting of experiments.

Parameter	Values	Unit
Plant size	600-800	EGW
Intake volume	0 - 10	m³ / h
Total biology volume	33	m³
Membrane surface area	525	m²
TS content (depending on waste water)	10 - 30	g / l
Input power	35	kW