Through the NSERC Chair municipal partners, the group has access to several full-scale water treatment plants and is routinely involved with projects conducted at partner sites or using water collected from these plants. Some of these plants employ ozonation, biofiltration, UV irradiation, and/or sand ballasted upflow clarification providing a wide variety of real world treatment processes to investigate.
Bench-scale filters for Geosmin & MIB removal studies at the R.C. Harris Filteration Plant in Toronto
Chemical Laboratory
Extensive chemical analysis facilities are available as support for the various research projects. Standard water quality parameters such as pH, turbidity, oxidant residual, alkalinity and total organic carbon (TOC) are measured on a regular basis. Other parameters are determined on demand depending on the particular research objectives.
Method development and implementation of existing methods typically focus on the analysis of organic compounds which is usually accommodated by sophisticated sample preparation and advanced instrumentation including a high pressure liquid chromatograph (HPLC), an ion chromatograph (IC), a gas chromatograph (GC) and a gas chromatograph coupled with mass spectrophotometer (GC/MS). Methods to measure halogenated and non-halogenated disinfection by-products (THM, HAA, aldehydes, organic acids) are well established. We have recently acquired a GC/MS/MS to analyze for pharmaceuticals, endocrine disrupters, and personal care products in water.
Recently, emphasis in drinking water treatment research has shifted to investigation of UV and membrane processes. The Chair has access to a collimated beam UV apparatus and work is underway to assess particle shielding during UV irradiation.
In addition, the Chair has two flat sheet membrane test units and several hollow fiber test units. The flat sheets are provided by membrane manufacturers or in some cases can be cut from spiral wound cartridges. The flat sheet and hollow fiber membranes are being evaluated for the removal of turbidity, particles, pathogens, pharmaceutically active compounds, and endocrine disrupting substances. Major initiatives are underway in the area of membrane biofouling.
A new addition to our laboratory is a dynamic particle analyzer. As well as being able to count particles within a wide variety of size ranges in water, this instrument captures a digital image of every particle contained within a volume (typically one or more ml) as the sample flows through a micro-fluidic cell.
The system software analyzes these images in real time to produce accurate particle size distributions and captures images meeting user-selected criteria. These images can help researchers to determine the origin and type of particles which are present (bacteria, protozoans, diatoms, cell debris, floc, GAC fines, etc.)
Microbiological Laboratory
The Chair team has a well-equipped Level 2 microbiology laboratory. Water and environmental samples can be processed for microbial analysis by various techniques including membrane filtration. Molecular biological detection of various microorganisms is also available by quantitative Polymerase Chain Reaction Unit (PCR).
General equipment include a Level 2 biohazard hood, centrifuges, UV/VIS spectrophotometer, incubators equipped with shakers and a C02 environmental chamber, autoclaves, and an ultrapure water system. The laboratory also has specialized equipment including:
- Two-phase contrast microscopes with UV fluorescence capability, and one with Nomarski DIC optics and an image analysis system
- Quantitative (real-time) PCR detection system which allows us to identify and enumerate pathogens in water
- Biolog® detection system for bacterial identification.
Methods are available for testing general water quality indicators, microbial pathogens, and various groups of environmental significance. Past research projects include detection of ammonia-oxidizing bacteria, Bacillus spores, bacteriophage, Gram-negative endotoxin, Cryptosporidium and Giardia, Campylobacter sp. and pathogenic E. coli. Current research projects are working to develop methods for quantitative PCR of a number of pathogens.
