Research Interests:

Biological Wastewater Treatment: Biological treatment systems are the most important means of removing nitrogen from wastewater. Very often, these systems utilize a single population of bacteria that are alternately exposed to aerobic conditions conducive to nitrification and anoxic conditions that allow denitrification. To maximize the rate of nitrogen removal, it is important that the bacteria adapt quickly to these changing conditions. We have demonstrated that bacteria changing from dissolved oxygen to nitrate as electron acceptors will experience a significant diauxic lag (period of no bacterial growth and nitrogen removal), sometimes lasting several hours. Obviously, significant lags can adversely affect the rate and, therefore, the economics of biological nitrogen removing processes. The goal of our research is to better understand the phenomenon of diauxic growth on oxygen and nitrate as alternate electron acceptors. Particle Processing: Size reduction to specifications is critical to the pharmaceutical and other industries. We are conducting experimental and modeling research on milling and classification.