Aerobic Granulation: A New Biotechnology for the Treatment of Contaminated Waters

As a reflection of the increased global attention on water and sanitation issues, the 6th Sustainable Development Goal has ensured the “availability and sustainable management of water and sanitation for all”. However, the negative impact of human development on ambient water quality has increased over time, and a vast range of new contaminants of emerging concerns (CECs) are now being discovered in surface water and groundwater systems. CECs can range from pharmaceuticals and personal care products to persistent organic pollutants utilized in many industrial processes. Currently, most conventional water and wastewater treatment methods are not able to effectively remove CECs originating from industrial and/or municipal sources. Aerobic granulation is a new biotechnology, more advanced than conventional activated sludge (CAS) process. It is a carrier-less cellto-cell self-immobilization phenomenon in which microbial biomass agglomerate as dense consortia packed with different bacterial species in a granular structure. When compared with CAS, granules have higher settling velocities, well-defined shape and structure, high biomass retention and better ability to withstand high organic loading. This technology can also substantially reduce sludge generation and land space requirements, ending up with a very small footprint. Aerobic granulation is perceived to be a promising new biotechnology for contaminated waters and wastewater treatment.