D. G. Allen

B.A.Sc., M.A.Sc. (Toronto), Ph.D. (Waterloo), F.C.I.C., F.A.A.A.S., P.Eng.

Room: WB221
Tel.: 416-978-8517
Email: dgrant.allen@utoronto.ca
Websites: http://www.labs.chem-eng.utoronto.ca/allen/ and www.biozone.utoronto.ca

Honours & Awards

The Professor Diran Basmadjian Teacher of the Year Award, Dept. of Chemical Engineering and Applied Chemistry
Fellow, Chemical Institute of Canada
Fellow, American Association for the Advancement of Science

Memberships

American Association for the Advancement of Science
American Association for Engineering Education.
Chemical Institute of Canada
Canadian Society for Chemical Engineering
International Water Association
Professional Engineers of Ontario

Research Interests

Environmental Bioprocess Engineering Research  
Bioprocess engineering is an exciting and growing field in which chemical engineering principles are applied to the use of biologically-based processes. The field is interdisciplinary, involving biotechnology, chemical engineering, microbiology and biochemistry and has a wide range of application areas including the production of food, pharmaceuticals, chemicals and the treatment of industrial wastes. Students can focus on fundamental engineering, chemistry and/or biology and interact with other faculty and industry on problems of economic and social importance.

One of my main areas of activity is in biological wastewater treatment, particularly as it relates to the pulp and paper industry. This is already applied in industry on a wide scale and continues to show enormous further potential, because of increasingly stringent environmental controls, an emphasis on minimum impact technologies, advances in biotechnology and the remarkable ability of microorganisms (wild or genetically engineered) to degrade a wide range of pollutants. The work to date has been on understanding and optimizing the biological treatment of chlorinated organic compounds and other bioactive compounds from kraft pulp mills, and we are also examining the potential for in-mill water re-use.

More recently, we have been focusing on biologically producing value added products (energy, biopolymers) from wastes. Specifically, we have a project to convert biomass produced during wastewater treatment into adhesives and biosurfactants or into activated carbon or biocomposite materials. We also are investigating strategies to optimize anaerobic conversion of wastewater into fuel. Another new area involves the utilizing wastewater and waste carbon dioxide to grow microalgae and convert it into fuels and chemicals.

The biological treatment of waste of gas streams is another exciting area of interest. The technology is being applied in Europe extensively and, because of its economic and environmental benefits will see increasing development and application in North America. The research includes projects on bed design, kinetics, microbiology and modeling.

Many of the projects involve looking more in depth at the microbial processes involved in collaboration with microbiologists Professors Roberta Fulthorpe and Steven Liss. In particular, we are interested in how bioreactor operation influences the microbial community and physical/chemical properties of biofilms and flocs in these treatment systems and how this in turn affects transport processes such as mass transfer and settling. We apply advanced molecular techniques such as DNA fingerprinting to probe microbial community structure and advance microscopy and physical chemical measurements to analyze the physical matrix (biofloc or biofilm).

Our projects also often involve collaborations among engineers, microbiologists, biologists and chemists and also provide opportunities for advanced professional development (communication skills, team skills, etc.) All of these areas have both engineering (e.g., kinetics, modeling, optimization) and microbiology (e.g., identification, monitoring, molecular biology) aspects and have received significant funding from government and industry through the Pulp and Paper Centre.

Selected Publications

Nadarajah, N., Allen, D.G. and R.R. Fulthorpe,2007. “Effects of Temperature Transient Conditions on the Divergence of Activated Sludge Bacterial Community Structure and Function”, Water Research 41, 2563-71.

Zhang, Y., S.N. Liss and D. Grant Allen, 2006. “The Effects of Methanol on the Biofiltration of Dimethyl Sulfide in Inorganic Biofilters”, Biotechnology and Bioengineering 95, 734-743.

Morgan-Sagastume F, and D.G. Allen. 2005. Physicochemical Properties and Stability of Activated Sludge locs under Temperature Upshifts from 30 to 45°C. Journal of Colloid and Interface Science. 281(1): 136-145.

Miller, M.J. and D.G. Allen, 2005. “Biodegradation of Hydrophobic Pollutants in Biofilms in Biofilters”, Environmental Science & Technology 39: 5856-5863.

Liao, B.Q., D.G. Allen, I.G. Droppo, G.G. Leppard & S.N.Liss, 2002, “Interparticle Interactions Affecting the Stability of Sludge Flocs”, J. Colloid. Interface Sci. 249 372-380.

Kong, Z., Farhana, L., Fulthorpe, R.R. and D. G. Allen (2001), “Treatment of Volatile Organic Compounds in a Biotrickling Filter under Thermophilic Conditions”, Env. Sci.Technol. 35, 4347-4352

Mohseni, M. and D.G. Allen (2000), “Biofiiltration of Mixtures of Hydrophilic and Hydrophobic Volatile Organic Compounds”, Chemical Engineering Science, 55, 1545-1558.

Tripathi, C. and D.G. Allen (1999), “Comparison of Mesophilic and Thermophilic Aerobic Biological Treatment of Sequencing Batch Reactors Treating Bleached Kraft Pulp Mill Effluent”, Wat. Res. 33(3), 836-846.