Derick G. Brown, Ph.D., P.E.
Microbial and colloidal attachment and transport through porous media
This research focuses on attachment and transport of microorganisms and colloids through both saturated and unsaturated porous
media. Key aspects of this work include (a) how surfactants - the key ingredient in detergents and other household
cleaners - affect microbial transport and (b) the linkage between lab-scale studies and field-scale transport. We have
facilities that allow experimental using 1-D and 2-D systems from the lab scale up to the meso-scale. Meso-scale systems include
a 1x1x9 meter horizontal flow system and a ~1.5x3 meter vertical flow system.
Links Between Microbial and Physiochemical Processes
My interests in this area are related to how microbial kinetics and physiochemical processes can be manipulated to enhance the remediation
of environmental contaminants and treatment of waste streams for renewable energy production. My research group is developing
novel ion-exchange technology for stabilizing anaerobic digesters to upset, with the goal of making them attractive options for sustainable
energy generation at industries that have highly-variable waste streams. We are also investigating the bioavailability
and biodegradation of hydrophobic and ionizable organic contaminants and are investigating novel applications of membrane processes
for biological treatment of nutrient-rich waste streams.
This research focuses on how bacteria interact with surfaces, both in terms of physiochemical processes and biological processes.
As part of this research, we developed a new theory linking the physiochemical charge-regulation process to bacterial bioenergetics
of attached bacteria. This theory describes how surfaces can enhance or inhibit bacterial activity, depending on the acid/base
functional groups on the two surfaces, and we have demonstrated these conditions through both experiments and theoretical modeling.
This research has implications on bacterial surface sensing, biofilm formation, and long-term survival under oligotrophic conditions.
Our overall goal is to design surfaces that passively alter microbial colonization and kinetics.
Interactions between microorganisms and surfaces