Biosorption in the activated sludge process

The activated sludge process is the most common wastewater treatment process in the developed world. Removal of organic matter, nitrogen, and phosphorous is accomplished by flocs containing living microorganisms. Both physical and biochemical processes contribute to removal of the target pollutants. Biochemical conversions in activated sludge can be modeled relatively accurately. It is also well-known that a large amount of organic matter and ammonium is rapidly taken up by the activated sludge upon contact. However, this physical biosorption process is still poorly characterized and typically not considered in the design of new treatment processes.

The goal of this project is to investigate the mechanisms and kinetics of biosorption of organic matter and ammonium by activated sludge. We will develop a high-throughput measurement technique to analyze how sludge and wastewater characteristics affect biosorption. We will then model biosorption phenomena in full-scale activated sludge processes. We expect that our results will be important for the operation and control of existing activated sludge processes as well as for the design of new sustainable processes that minimizes energy consumption and maximizes energy recovery from the wastewater.