Grant: Discovery Grants Program - Individual

Protecting the environment through infrastructure that supports modern society is critical to providing a safe and high quality of life; and is a particularly important goal for Civil Engineering. My NSERC-supported research explores the interface of microbiology and engineered systems for biological wastewater treatment. The goal is to better integrate knowledge of biological, chemical and physical characteristics of microbial structures (flocs and films) and their behaviour, that are associated with traditional suspended growth systems, and advanced technologies based on fixed-film processes. The specific objectives include: i) advancing the understanding the role of particular glycoconjugates and adhesin proteins associated with extracellular polymeric substances (EPS) of floc and in microbial interfaces; ii) elucidating factors affecting floc and film properties in the suspended and attached populations in integrated fixed film activated sludge (IFAS) systems; iii) achieving a better understanding of the microenvironment in aerated-membrane bioreactor biofilms, particularly with respect to electrochemical gradients (oxygen and redox) and EPS, in relation to biofilm properties and stability at the membrane-film interface; and iv) training of research students in environmental engineering and environmental biotechnology, and the transfer of novel tools and approaches to the investigation and development of advanced environmental technology. We employ both bench-scale and pilot-scale systems designed to simulate wastewater treatment processes and are run under well-controlled conditions in specific ways to influence floc and film properties. Consultation with engineers and operators will enable us to integrate this approach with the experience of full-scale systems of different configurations. We continue to build upon our biochemical and molecular tools developed in our laboratory to advance the importance of physicochemical properties of microbial structures, and uniquely employ advanced optical microscopy (confocal imaging, atomic force microscopy and Raman confocal imaging) and high resolution scanning transmission electron microscopy that permits us to establish structure-function relationships.