Environmental Engineering Commons^™

Effect Of Pretreatment Of Resin Acids On Anaerobic Digestibility Of Pulp And Paper Mill's Primary Sludge, Sreejon Das

Electronic Thesis and Dissertation Repository

Pulp and paper (P&P) mills’ wastewater contain high concentrations of resin acids (10–10,000 mg/L) which are toxic to aquatic organisms. In mill’s primary and waste activated sludge treatments reduced concentrations of resin acids in effluent; however, most of the resin acids are ultimately ended up in sludge after primary and secondary clarification due to their extreme hydrophobic nature (log K_ow 6.0). Nevertheless, adsorbed resin acids on the surfaces of anaerobes and substrates affect anaerobic digestion (AD) process negatively. The objective of the present work was to determine the effect of pretreatment of thermomechanical pulping mill’s primary sludge (TMP-PS) on …

Overcoming Technological Challenges For The Commercialization Of The Circulating Fluidized Bed Bioreactor For Municipal Wastewater Treatment, Michael J. Nelson

Electronic Thesis and Dissertation Repository

The fluidized bed bioreactor as an attached growth wastewater treatment process has demonstrated advantages over suspended growth processes for municipal wastewater treatment applications. However, previous studies have also demonstrated potentially serious disadvantages in terms of energy consumption and maximum reactor size of high flow applications.

In this work, a cost analysis using the CapdetWorks, supplemented by calibrated model data taken from GPS-X was performed to determine the cost effectiveness of the circulating fluidized bed bioreactor (CFBBR). This study demonstrated that the CFBBR is most cost competitive at low flow below 5 MGD. A 10%-20% reduction in net present values on …

Treatability Of Micropollutants And Microplastics Using Selected Wastewater Treatment Processes, Juan Li

Electronic Thesis and Dissertation Repository

Micropollutants and microplastics are ubiquitously detected in environment, which are directly linked to human health and ecosystems safety. Conventional wastewater treatment plants (WWTPs) are regarded as a major source for discharging these contaminants into environment. Therefore, it is of great significance to study the behavior of these pollutants and their removal potential in WWTPs. This work investigated specific treatment processes to determine their efficiency in removing target micropollutants and microplastics.

Primary treatments in WWTPs are first step to removal solid particle and other floated materials from the water stream. Therefore, the process is important for microplastics particles. The behavior of …

Experimental Simulation Of Tornado-Like Vortices And Their Impact On High-Rise Buildings, Arash Ashrafi

Electronic Thesis and Dissertation Repository

One of the most crucial research areas in wind engineering is tornadoes due to the widespread damages to infrastructure and the environment in North America and other parts of the world. The proper scaling of tornadoes in experimental facilities, generating tornado-like vortices (TLVs) is, therefore, an essential part of evaluating tornado-indued damages on engineered buildings. The capability of producing TLVs of length scales in the range between 1:300 and 1:150 inside the Wind Engineering, Energy and Environment (WindEEE) Dome at Western University has already been demonstrated using only one mode of the full potential of this simulator. A new mode …

Active Fluids: Rheological Properties And Response To Light Of Suspensions Of Synechocystis Sp. Cpcc 534, Zahra Habibi

Electronic Thesis and Dissertation Repository

Despite our current understanding of active fluid mechanics, more knowledge is required to fully understand their rheological properties, response to light, and details of the interactions between cells in diluted suspensions.

The focus of this thesis is on investigating the rheological properties of suspensions of cyanobacterium Synechocystis sp. CPCC 534 under shear, induced by stirring. Experiments were conducted at different stirring rates and results are compared with the stationary condition. A notable increase in growth and biomass of Synechocystis sp. under various shear conditions was observed and the yield was nearly doubled. Besides, the data showed Newtonian behavior for suspensions …

Inter-Disciplinary Characterization Of Streambed Heterogeneity And Its Influence On Groundwater-Stream Water Interactions, Kyle Robinson

Electronic Thesis and Dissertation Repository

It is well recognized that groundwater-surface water interactions influence the quantity and quality of various hydrogeological systems (rivers, lakes, streams). Groundwater-stream systems are an important investigative area for understanding fate and transport of nutrients and chemicals within the stream. While traditional methodologies are established to provide measurement and mapping of the spatial distribution of groundwater-stream interactions and exchange fluxes across a streambed, many can be invasive, labour intensive and suffer from low sampling density. The complexity in such systems is due largely to the heterogeneous nature both spatially and temporally. Given the strong control by streambed lithology on groundwater-surface water …

Long-Term Field Performance Of Geomembrane-Lined Cover Systems At Mine Waste Rock Piles, Deanna Hersey

Electronic Thesis and Dissertation Repository

Mine waste rock piles (WRPs) are anthropogenically created landforms at active and former mining sites that can generate and release highly toxic acid mine drainage (AMD) to the environment. A common solution to control AMD generation is the use of cover systems at the WRPs to isolate the reactive waste from water and oxygen in the atmosphere. Geomembranes exhibit the characteristics needed to be highly effective barriers to atmospheric influx; however, knowledge on their performance at in-service WRPs is limited. The objective of this thesis is to comprehensively assess the field performance of geomembrane-lined cover systems for limiting meteoric water …

Practical Issues In Floodplain Mapping Over Large Regions, James Eric Braden

Electronic Thesis and Dissertation Repository

Flooding events are among the costliest and most frequent natural hazards occurring in Canada. Floodplain mapping is a non-structural flood management strategy that involves the formulation of hydrologic and hydraulic models to produce maps which predict extent and depth of floods. Practices and availability of floodplain mapping vary across Canada. The current state of floodplain mapping across Canada has been identified and reviewed. Vast areas of flood prone regions across Canada have been identified as not having floodplain maps or lacking updated ones. Large region floodplain maps have been recently introduced and can cover national and global regions. Limitations of …

Modelling And Investigating The Impact Of Thermal Hydrolysis Pretreatment On The Anaerobic Co-Digestion Of Sewage Sludges And Food Waste, Amr Ismail

Electronic Thesis and Dissertation Repository

In this study, the impact of thermal hydrolysis pretreatment (THP) on the mono- and co-digestion of thickened waste activated sludge (TWAS) and food waste (FW) was carried out at temperatures of 150, 170, 190, and 210 ˚C for a contact time of 30 min and mixing ratios of 90:10, 70:30, and 50:50 on a volumetric basis in batch anaerobic tests. Thermal hydrolysis influenced the solubilization of the particulate organic constituents of TWAS, reduction in volatile suspended solids (VSS) and particle size with the increase in temperature to 210 ˚C, achieving a reduction in VSS up to 62% and a reduction …

Urban Heat Mitigation For Current And Future Conditions: A Case Study For Downtown London On, Maryam Shams

Electronic Thesis and Dissertation Repository

The urban heat island is a phenomenon wherein urban areas experience warmer temperatures than their surrounding rural areas. Techniques to reduce excess heat in urban environments are known as heat mitigation or heat island mitigation solutions, with the intent that they reduce urban temperatures. This research presents an investigation on the impacts and effectiveness of urban heat mitigation techniques on improving the outdoor thermal conditions of downtown London, Ontario. The impact of increasing vegetated areas and applying higher albedo materials for road pavements is assessed with ENVI-Met software for current and future summer weather. Furthermore, investigations were conducted for current …

Assessing The Evolution Of Mine Water Quality With Empirical 'First-Flush' Models, Patrick J. Merritt

Electronic Thesis and Dissertation Repository

Coal mining activities can leave an extensive network of abandoned underground workings that gradually flood after operations cease. This rising mine water, with low pH and high sulfate, acidity, and metals can lead to uncontrolled releases of harmful acid mine drainage to the environment. Treatment plants are used to extract and treat the mine water to maintain its elevations below suspected discharge zones. Accurate predictions of long-term water quality is highly challenging due to the complexity and volume of the underground workings. As numerical models have difficulty recreating complex mine pool geometry and hydrogeochemical processes, empirical models that are based …

Integrated Modelling Of Wastewater Treatment And Sewer Processes - Interactions Of Fluid Flow, Mass Transfer, And Biochemical Reactions, Ahmed Khalil

Electronic Thesis and Dissertation Repository

Numerical modelling of wastewater management systems is crucial for investigating alternative designs and developing strategies for operation and control that improve the performance of the treatment stage (such as improving the aeration systems in activated sludge systems). Modelling can also help operators to mitigate common problems that arise from unwanted biochemical conversions in the sewer networks (such as the production of sulfide and methane). Therefore, this work focuses on two major areas related to modelling wastewater management systems. First, it seeks to develop more accurate models for aeration systems in activated sludge reactors. Second, it seeks to study the mathematical …

Anammox Process For Nitrogen Removal: Development Of Sustainable Gel Beads And Its Application In Fluidized Bed Reactors (Fbrs), Mohammad M I Chowdhury

Electronic Thesis and Dissertation Repository

Biological nitrogen removal (BNR) processes have been widely used for removing wastewater nitrogen because of effectiveness, economics, and environmental friendliness. Considering the energy requirements for nitrification and need for external carbon for denitrification in conventional BNR processes, anaerobic ammonia-oxidizing bacterial (anammox) processes facilitate energy-neutral or net energy positive biological treatment as well as reduce operational costs because of reduction in aeration energy, which constitutes 50%-60% of the overall energy consumption at municipal wastewater treatment plants, elimination of external organic carbon requirements, and lower sludge production. However, one of the major challenges in the practical application of the anammox process is …

Cellulose Biodegradability And Its Impact On Enhanced Biological Phosphorus Removal, Moustafa Ibrahim Elbahrawi

Electronic Thesis and Dissertation Repository

Cellulose from toilet paper contributes approximately one third of the influent organic suspended solids (TSS) to wastewater treatment plants and is a key target for resources recovery. Cellulose recovery is beneficial as it reduces the required energy for treatment and biosolids treatment cost. Hence, understanding the hydrolysis of cellulose in wastewater which is mainly affected by temperature and the solids retention time (SRT), is a major key to determine the optimum location for its recovery. In order to assess the impact of temperature and SRT on cellulose degradation, this study investigated the biological aerobic degradation of cellulose in four laboratory-scale …

Assessment Of The Impacts Of Climate Change, Land Cover Transition, And Internal Climate Variability On The Hydrology Of A Forested Watershed, Vahid Mehdipour

Electronic Thesis and Dissertation Repository

In this study, the impacts of climate and land cover (LC) changes on the hydrologic processes of the Batchawana watershed in Central Ontario are assessed. Batchawana is a snow-dominated forested watershed with coniferous, deciduous and mixed trees and numerous small lakes. A semi-distributed hydrological model, based on the Raven hydrological framework, is calibrated and validated using ground-based observations for 1981-2001 and 2002-2011, respectively. Eight downscaled General Circulation Models (GCMs) that participated in the Coupled Model Intercomparison Project Phase 5 (CMIP5) and three large ensembles (50 members) of Regional Climate Model (RCM) simulations, under the Representative Concentration Pathway (RCP) 8.5, are …

Production Of Engineered Carbons From Secondary Waste Streams For Environmental Applications, Ghazaleh Chegini

Electronic Thesis and Dissertation Repository

Pyrolysis and activation were used in this thesis to produce biochar and activated carbon from industrial digestate and hydrochar materials. In the first part of thesis, digestate derived biochars were obtained by varying the pyrolysis heating rate (10, 80, 100, 200, >1000 °C·min^-1) and temperature (300 to 600 °C) to modify their soil-related characteristics (i.e., nutrient leachability, carbon stability, and heavy metal adsorptive capacity). The biochar produced at a temperature of 500 °C and heating rate of 10 °C·min^-1 was also activated under using CO₂ at 800 °C with different holding times (0.5-2 h). Results indicated …

Northern Tornadoes Project. Annual Report 2020, Northern Tornadoes Project

Project Reports

NORTHERN TORNADOES PROJECT:

IMPACT AT A GLANCE

Entered into working partnerships with University of Manitoba, York University and The Weather Network

Acquired cutting-edge drone technology, allowing us to obtain high-quality, highly accurate damage survey data and images

Obtained an advanced drone licence, allowing us to fly drones longer distances without keeping the drone in sight

Conducted 409 NTP investigations, 292 Planet satellite surveys, 31 ground surveys, 24 drone surveys and 4 aircraft surveys

Verified the occurrence of 77 tornadoes across Canada in 2020. NTP investigations increased the verified tornado count by 166%

Created a more useful, user-friendly Dashboard and Open …

Impact Of Artisanal And Small-Scale Mining On Water Bodies And Treatment: The Case Of Birim River Basin In Ghana, Adwoa Boadua Yirenkyi Fianko

Electronic Thesis and Dissertation Repository

Water bodies, the source of drinking water for many rural households in mining areas are at risk of contamination due to artisanal and small-scale mining (ASM) activities. Water quality, therefore, remains a topical issue for policymakers and researchers.

This research sought to achieve three objectives: firstly, to evaluate the effectiveness of existing policies and regulations about ASM in protecting waterbodies. Secondly, to determine the impact of ASM on waterbodies, health and livelihood of inhabitants in mining communities and thirdly, to remove heavy metals from water using locally available bio-adsorbents such as moringa seeds, coconut and corn husks.

A survey of …

Enhanced Primary Sludge Fermentation And Anaerobic Digestion For Integrated Carbon Upgrade And Resource Recovery, Gholamreza Bahreini

Electronic Thesis and Dissertation Repository

The emerging paradigm shift towards renewable resource recovery, and energy minimization in municipal wastewater treatment plants (WWTPs) coupled with increased concern over nutrients-related eutrophication accelerated the development of biosolids treatment technologies for simultaneous waste minimization, resource recovery, and carbon upgrade. Biological nutrient removal (BNR) processes, often need excess carbon source to meet stringent quality standards. Despite successful use of sludge fermentation liquid to enhance the BNR, different techniques, are applied to improve the low conversion yield of fermentation and optimize resource recovery. In this context, insights on the impact of two commonly used primary treatment techniques (i.e. conventional primary clarifier …

Experimental Study Of Tornado-Induced Pressures, Aya Kassab

Electronic Thesis and Dissertation Repository

The increased devastation associated with tornadic flow-fields in terms of human lives or destruction of properties and their subsequent economic losses highlights the significance of understanding the tornado vortex structure, particularly near the ground where the majority of this destruction happens. While the body of research in this area is increasing there is a lack of resolution associated with physical near-surface measurements in tornado-like vortices (TLVs) and the effects of translation, surface roughness, and surface vortex dynamics are not yet well understood.

In order to address these gaps, high spatial and temporal surface pressure measurements were carried out at WindEEE …