Breathe in - with biofilm. The Membrane Aerated Bioflm Reactor consists of two main components the membrane and the Biofilm. The Biofilm which is a consortia of micro-organisims growing attached to each other and in most cases also to a surface, is what actually breaks down the pollutants in the wastewater. Biofilm or Fixed Film technologies have been around for over 100 years. With trickling filters one of the oldest wastewater treatment technologies in existence. Up until recently all biofilm systems whether submerged or non-submerged have been co-diffusional biofilms. This means that all the nutrients and oxygen diffuse into the biofilm together from the exposed surface. The material on which the biofilm is attached is inert and does nothing apart from provide the surface upon which the biofilm grows, which means there is no need for recovery of the biomass as its always in the reactor. These co-diffusion biofilms have limited reaction rates due to diffusional limitation within the biofilm.
NASA is hard at work tackling the challenges of space travel and dreaming up technologies to meet those challenges. Researchers are examining wastewater recovery systems robust enough for use on long term space missions. Biological treatment has been the primary focus, with specific thrusts in developing a biological treatment system that may be operated with minimal crew maintenance and low energy and mass requirements.