In the presence of hydrogen peroxide (H2O2), soybean peroxidase (SBP) extracted from the soybean seed coat catalyzes the polymerization of various chlorinated phenols from wastewater. The resulting polymer precipitates from solution and can be removed through a simple sedimentation or filtration process. To date, the majority of the research has focused on horseradish peroxidase (HRP) as the enzyme source. Recently, researchers have discovered that SBP is thermally more stable and can work in a different pH range than HRP. Since the soybean seedcoat is a waste product of the soybean industry, developing a value-added process to utilize the waste would be economical. Several limitations need to be resolved prior to this enzymatic process becoming a legitimate treatment. For instance, peroxidase enzyme (PE) inactivation is a primary concern in trying to make the process more viable. Researchers have postulated that the PE is inactivated by entrapment into the forming polymers. To prevent such occurrences, high molecular weight substance such as gelatin and polyethylene glycol (PEG) have been added to solution. PEG 8000 provides a significant increase in protection compared to PEG 3350, a standard additive used for HRP. To date, researchers studying SBP as an alternative to HRP have focused mostly on the treatment of phenol. The effectiveness of SBP to treat chlorinated phenols is presented in this research. Some of the parameters studied include the effects and interactions of temperature, reaction time, pH, SBP concentration, PEG molecular weight, PEG concentration, type of substrate, substrate concentration, mode of substrate addition, mode of SBP addition and mode of H2O 2 addition. SBP was found to be a suitable alternative to HRP offer similar results and in some cases, improved the results.

This project tested at the field scale, five on-site, non-proprietary bioremediation processes on weathered petroleum hydrocarbons from a fire fighter training area. Two bioremediation processes based on fungi (commercially produced white rot fungus, Pleurotus ostreatus, and aged, coarse wood chips, 'compost', with naturally occurring fungi) were applied with variations and compared to one control: a typical static biopile. An elevated-face compost turner was used to turn the soil in selected windrows for aeration. Statistically-based sampling was employed and quality control measures were enforced for sampling and analysis. The treatment options examined for the contaminated soil were: (1) white rot fungus and compost, (2) compost, poultry manure and turning, (3) compost, synthetic nitrogen-phosphorous-potassium fertilizer, and turning, (4) compost, the above synthetic fertilizer, and no turning, and (5) the above synthetic fertilizer, and no turning (static biopile). The compost and poultry manure process performed the best, remediating 35 tonnes of soil contaminated with 6000 mg/kg of mineral oil and grease (MOG) to the remediation criteria of 1000 mg/kg in 19 days and to less than 300 mg/kg in less than 56 days. The net rate of bioremediation was 100 mg/kg/day of MOG. The estimated cost of this process for commercial applications, excluding labour, excavation and site preparation, was $18 to $29 per tonne, depending on the cost of the poultry manure.

Following up on a body of research commencing with the Wastewater Allocation Study of the South Nation River [1992] in Eastern Ontario, the problems facing watershed managers are assessed. Following a systems engineering methodology, the WMDSS requirements are decomposed and ranked in order of priority. This yields a ranking for development of tool and information functional groups to support the following assessment types: surface water quality, surface levels and flows, integration, groundwater flows/levels, rainfall/runoff modelling and time series analysis. Functional analysis then provides the architecture and data flows necessary to meet system requirements: primary sub-systems for management of the database, knowledge base, model base, graphical user interface and output reporting are characterised. The current state of the science of watershed management is assessed with a view towards meeting the identified system functionality. With a comprehensive object-oriented analysis and design (OOA/D), the framework necessary for production of a contemporary Watershed Management Decision Support System (WMDSS) is outlined and assessed in light of current tools in use today. (Abstract shortened by UMI.)

The feasibility of anaerobically treating a leachate from a landfill site in the Ottawa-Carleton Region, ON, was studied. The levels of specific pollutants present in the leachate, COD, Fe, B and Ba, were required by the landfill owners to be treated in order to meet the local sewer user bylaw (SUB) discharge limits. The leachate had a high COD concentration (from 14 to 40 g COD L-1); however most of the organic content was readily biodegradable (up to 98%). The studied leachate was concluded to stimulate anaerobic bacterial microbial activity. The filtration of the leachate by peat moss was found to be an excellent means of removing suspended solids. The core experiments of this work were the treatment of the leachate by the combined peat-filter-UASB reactor process. Three series of reactor runs were conducted; feed leachate COD concentration and reactors flow rates were varied in order to mimic seasonal landfill leachate conditions (spring, summer and fall conditions). Finally, the removal of soluble inorganic ions by the combined treatment was studied. (Abstract shortened by UMI.)

Soybean peroxidase (SBP) shows potential to remediate water-soil systems, yet relatively little is understood about its reaction in soil environments. While the potential may exist for the use of SBP in soil systems, too many difficulties and unknowns face the research of SBP to soil systems. This study will focus on the use of SBP in soil slurries as a stepping block to future research with soil systems. This study investigates the use of SBP to remediate 2,4-dichlorophenol (2,4-DCP) in wastewater when soil is present in the reactor vessel. Characterization of 2,4-DCP binding to soil (peat moss and silica sand) revealed that the binding was effected by the pH and the mass of the soil. The determination of enzyme kinetic constants and enzyme reactions was not examined in this study. The application of SBP to reactors with wastewater and soil has the potential to improve or decrease removal, under different reactor conditions, versus wastewater only systems. Assumptions regarding the sorption of the 2,4-DCP to soil allowed conclusions to be made regarding the activity of the SBP. (Abstract shortened by UMI.)

The objective of this work is to improve the pervaporation separation characteristics of polydimethylsiloxane (PDMS) membranes by imbedding organo-clay particles in the polymer structure. Montmorillonite is a clay mineral with a 2:1 layered structure. The negative charges on its layers due to the compositional inhomogeneities are counterbalanced with inorganic cations. Organo-montmorillonite is formed when the inorganic cations are exchanged with organic cations. The nature, type and structure of exchangeable cations on montmorillonite strongly influence their sorptive characteristics. Different combinations of these factors will produce very different interlayer environments. Tetraphenylphosphonium (TPP) and tetraalkylammonium cations (TAAn; where n is the number of carbon of the chain) were intercalated into montmorillonite to form a series of organo-clays (TPP-M; TAAn-M). The organo-clay-PDMS composite membranes (TPP-M-PDMS: TAAn-M-PDMS) were prepared by adding the organo-clays into the PDMS solution. Pervaporation experiments of dilute 1,2-DCE and benzene solutions were performed using organo-clay-PDMS composite membranes. The effects of the nature of organo-clays, of the organo-clay content, and of the temperature and downstream pressure as operating variables on the membrane performance were investigated. (Abstract shortened by UMI.)

Granular activated carbon (GAC) is used in municipal drinking water treatment plants for the removal of organic compounds (natural and synthetic), taste and odour compounds, as well as for the removal of disinfection by-products (DBPs). Many alternative technologies for GAC regeneration, such as bioregeneration, chemical regeneration, chemical desorption regeneration, and steam regeneration, have been tested in attempts to overcome the shortcomings of thermal regeneration. In this study, the suitability of electrochemical regeneration for municipal drinking water systems was investigated. Three different sample types were obtained; virgin, field spent and field-thermally reactivated GAC. The field spent samples were electrochemically regenerated at 10, 50, 100 and 200mA in a divided cell electrochemical reactor for 5 h. The virgin, the thermal and the electrochemical regenerated samples were analysed for aqueous NOM adsorption, iodine number, surface chemistry, pore size distribution and surface area to evaluate the regeneration efficiency and to characterize the regeneration. The electrochemical reactor was able to regenerate 8--15% of the adsorption capacity of the field spent GAC compared to approximately 100% regeneration efficiency for the thermally regenerated samples. (Abstract shortened by UMI.)

Fractured rock aquifers consist of complex flow systems that impose several constraints on cleanup efforts. Remedial techniques in such aquifers are influenced by diffusion of contaminants into the rock matrix and the subsequent back diffusion into the fracture. In particular, the back diffusion process can release a low concentration of contaminant into the groundwater for an extended period of time alter the main source of contamination is removed from the fracture network. Biofilms have been defined as cells immobilized on a solid surface and embedded in a gel matrix of extra-cellular polymeric substances (EPS) excreted by microorganisms. Biofilms can be stimulated on rock surfaces to act as a barrier in groundwater systems, which influences hydraulic properties of the fractured media as well as the rate of contaminant transport between the rock matrix and the fracture. The main objective of this study was to assess the potential of a biofilm to limit diffusion between the host rock and fracture. The impacts of different types of microorganisms on the diffusion rate were compared, and the performances of the tracers employed in diffusion experiments were evaluated. P. putida, E. coli and an indigenous groundwater population were used to grow biofilm on porous ceramic disks with nominal pore diameter of 6 mum. Disks were installed into stainless steel double-reservoir cells. The source reservoirs were spiked to obtain initial concentrations of 1500 ppm of bromide and 5000 ppb of Lissamine. In total, 17 experiments were conducted to assess the diffusion. Finally, a semi analytical model was used to interpret the geometric factors (tortuosity) of the porous media and the impacts of the biofilm on the effective diffusion coefficient. Results, estimated from bromide and Lissamine concentration profiles, did not suggest a significant impact of biofilm on the diffusion through the ceramic disks. This could be due to heterogeneity of biofilm structures, loose structures of developed biofilms, lack of biofilm penetration into the pores inside the disks as a result of nutrient overloading or biofilm decay/detachment during the test. In addition, Lissamine did not appear to perform as a conservative tracer in some cases where mass balance calculations indicated a loss of dye. It was recommended to characterize the biofilm structure as well as the biofilm impregnated zone, and to adjust the nutrient loading in order to obtain a more packed structure for the biofilm developed by small size bacteria. Recommendations also included a thorough evaluation of Lissamine behaviour as a conservative tracer.

The increasing concern over potential health effects of pharmaceutically active compounds (PhACs) and endocrine disrupting compounds (EDCs) in drinking water has led to an increase in assessment of drinking water treatment plant efficiencies at removing these emerging micropollutants. For the most part, tight commercial membrane processes such as nanofiltration (NF) and reverse osmosis (RO) successfully eliminate PhACs and EDCs, however these are costly processes and infrequently implemented in North American treatment facilities. The more frequently used microfiltration (MF) and loose ultrafiltration (UF) membranes are ineffective in the removal of these compounds. This thesis focuses on developing tight charged ultrafiltration (UF) membranes which could effectively remove PhACs and EDCs from drinking water without compromising flux and cost. The approach centers on developing the membrane surface charge by incorporating charged surface modifying macromolecules (CSMMs) as additives. Four CSMMs (MDI-PPG-HBS, MDI-PEG200-HBS, MDI-PEG400-HBS, MDI-DEG-NDS) were evaluated at three different casting conditions for poly(ether sulfone) (PES) based membranes. The modified membranes were compared to controls (without CSMMs) and one commercial membrane (NF270, Dow/Filmtec). Membrane properties including flux, molecular weight cut off, surface porosity, charge and hydrophilicity were evaluated and compared to the removal of four representative PhACs and EDCs (sulfamethazine, carbamazepine, bisphenol A and ibuprofen) at the mg/L-level. The experimental membranes only achieved a temporary partial removal of the PhACs and EDC tested, thus further development is required. Given the temporary target compound removal and the large membrane pores, size exclusion and charge repulsion are not the dominant removal mechanism. From the removal pattern, and the fact that removal increased with increasing solute hydrophobicity, it is assumed that initial removal is caused by adsorption to the membrane. The membranes developed were tight by conventional ultrafiltration standards but did not achieve the performance desired. In general, it was found that the CSMM-modified membranes did not significantly outperform the control membranes. CSMM-modified membranes tested generally produced less hydrophilic membranes with increasing pre-gelation time or PES concentration, in comparison to the control membranes. Pre-gelation time (i.e., three minutes versus no pre-gelation time) increases membrane porosity, and therefore flux is increased, without compromising removal. Increased PES concentration (i.e., 20% PES in comparison to 18% PES) yields more distinct effects from the different CSMMs. From these results, the most promising casting condition appears to be 20% PES and the CSMMs achieving the best removal are MDI-PEG 400-HBS and MDI-PPG-HBS. As increased surface porosity was achieved, continuing this line of research by optimizing membrane preparation conditions to decrease the pore size may produce the desired characteristics. It is recommended that further tests be performed at increased PES concentrations and with pre-gelation time to achieve better results.

Equilibrium adsorption properties are studied on zeolites for the application of upgrading biogas from landfills. Pure adsorption isotherms of carbon dioxide (CO2) and methane (CH4) measured with a constant volume apparatus. The Henry's Law constant and the heat of adsorption for NaLSX is also determined. The adiabatic working capacity and selectivity of four adsorbents is compared. NaLSX showed the highest capacity for CO2 at elevated temperatures. The binary equilibrium of CO2/CH4 on NaLSX is measured in a modified gas chromatograph at total mixture pressures of 1 and 3.3 atmospheres. The adsorbed phase is dominated by CO2 with a selectivity of 20 to 100 for the separation of CO2 and CH4. The increase in total pressure resulted in an increase in adsorbent capacity and a decrease in selectivity. Finally, an economic analysis relates landfill size to PSA operational costs and returns.