Master of Science / Department of Biological and Agricultural Engineering / Stacy L. Hutchinson / The energy sector needs to transition to renewable energy to provide energy and economic security in the future (Murray & King, 2012). Liquid biofuels are an important renewable fuel in this transition because they are the preferred renewable energy source in the transportation sector (Lange, 2007), and the only renewable energy alternative for the aviation industry [International Air Transport Association (IATA), 2015]. Biofuels produced from food crops (first-generation biofuels) are being produced at an industrial scale, but they create several environmental and social conflicts (Mohr & Raman, 2013). Currently, there is a demand for the next generation of biofuels to resolve the environmental and social conflicts associated with first-generation biofuels. Salicornia, a salt tolerant oil seed crop (Panta et al., 2014), is one feedstock that might be able to resolve some of those conflicts because it can be irrigated with saline water (Warshay et al., 2017). The ability of Salicornia to tolerate saline environments suggests that it might be able to be cultivated in a hydroponic system designed to treat industrial wastewater. A hydroponic system designed to treat industrial wastewater and produce Salicornia as a biofuel feedstock could prevent some of the detrimental effects of industrial sources of saline water on terrestrial and aquatic ecosystems (Gerhart et al., 2006), and produce a feedstock that resolves some of the issues with first-generation biofuels. The first step in the development of the proposed hydroponic system is to determine if Salicornia can be cultivated with industrial wastewater in a hydroponic system. Studies were conducted with two sources of industrial wastewater, Flue Gas Desulfurization (FGD) wastewater and Cooling Tower Blowdown Water (CTBW), to determine how the composition of water affects the germination, survivability, early seedling growth, and lignocellulosic composition of Salicornia. The composition of water was shown to have no effect on seed germination and visual signs of phytotoxicity. These studies found that full strength CTBW and 20% FGD wastewater could be used to cultivate Salicornia in a hydroponic system if nutrients are added. Full strength FGD wastewater was shown to have a negative impact on seedling growth. These studies also found that Salicornia is not a good lignocellulosic biofuel feedstock because of its low lignocellulosic composition (e.g. 14.9-9.1% glucan, 13.2-6.7% xylan, 5.2-2.4% arabinan, and 9.8-6.2% lignin). However, a large percentage of the extractives content is unidentified and could have a monetary value. Additional research is needed to determine if a hydroponic system that cultivates Salicornia is able to provide any water quality treatment.

Orientador: Roberto Alves de Oliveira / Banca: Luiz Carlos Pavani / Banca: Tania Leme de Almeida / Banca: Valeria Del Nery / Banca: Giovana Tommaso / Resumo: Avaliou-se o desempenho de doisconjuntosde reatores UASB instalados em série, notratamento de águas residuárias de suinocultura, e o reúso dos efluentes na adubação de milho e sorgo. Os conjuntos I e II foram compostos por dois reatores UASB em série com volumes de 908 e 350 L e de 908 e 188 L, respectivamente. No conjunto II foi realizado o pós-tratamento em um reator aeróbio operado em bateladas seqüenciais (RBS) de 3000 L. Os tempos de detenção hidráulica (TDH) aplicados no reator do primeiro estágio (R1) foram de 72, 54 e 42 horas em ambos os conjuntos. As cargas orgânicas volumétricas (COV) aplicadas no R1 variaram de 6,9 a 12,6 kg DQOtotal (m3 d)-1 e de 7,5 a 9,8 kg DQOtotal (m3 d)-1, dos conjuntos I e II respectivamente. Nos sistemas de tratamento anaeróbios, as eficiências médias de remoção de DQOtotal, nitrogênio Kjeldahl (NK) e fósforo total (P-total) no conjunto I atingiram 96, 68 e 64%, respectivamente, e no conjunto II, 95, 61 e 60%, respectivamente. Para Cu, Fe, Mn e Zn, as eficiências médias de remoção dos sistemas de tratamento anaeróbio, no conjunto I atingiram 94, 88, 78 e 92%, respectivamente, e no conjunto II, 82, 80, 81 e 90%, respectivamente. Com a inclusão do RBS aeróbio no sistema II, as eficiências aumentaram para valores de 98, 73 e 82% para DQOtotal, NK e P-total, respectivamente, e de 88, 91, 86, 99 e 99,3%, para Cu, Fe, Mn, Zn e coliformes termotolerantes, respectivamente. O reúso dos efluentes tratados e do dejeto bruto, não promoveu mudanças na produtividade do milho e do sorgo, porém, a aplicação dos efluentes tratados elevaram as concentrações de N prontamente disponível para as plantas no solo. Mesmo aplicados em doses muito maiores comparativamente ao dejeto bruto, os efluentes tratados promoveram menor contaminação do solo por coliformes totais e termotolerantes / Abstract: The performance of two sets of UASB reactors installed in series was evaluated, for treatment of swine wastewater, and reuse of effluent as fertilizer for corn and sorghum. The sets I and II were composed of two UASB reactors in series with volumes of 908 and 350 L and 908 L and 188, respectively. In set II was performed after treatment in an aerobic reactor operated in sequencing batch mode (RBS) of 3,000 L. The hydraulic retention time (HRT) used in the first stage reactor (R1) were 72, 54 and 42 hours in both sets. The organic loading rate (OLR) applied on the R1, ranged from 6.9 to 12.6 kg total COD (m3 d)-1 and 7.5 to 9.8 kg total COD (m3 d)-1 in clusters I and II respectively. In anaerobic treatment systems, the average removal efficiencies of total COD, Kjeldahl nitrogen (NK) and total phosphorus (total P) in the set I reached 96, 68 and 64% respectively, and set II, 95, 61 and 60%, respectively. For Cu, Fe, Mn and Zn, the average removal efficiencies of anaerobic treatment systems, on the whole I reached 94, 88, 78 and 92% respectively, and set II, 82, 80, 81 and 90% respectively . With the inclusion of aerobic RBS in the set II, increased efficiencies, reaching values of 98, 73 and 82% for total COD, total-P and NK, respectively, and 88, 91, 86, 99 and 99.3% for Cu , Fe, Mn, Zn and thermotolerant coliforms, respectively. The reuse of treated effluent and raw manure, did not promote changes in the productivity of maize and sorghum, however, the application of treated effluent increased concentrations of N readily available for plants in soil. Even in much larger doses applied compared to the raw waste, the treated effluent, promoted soil contamination by total coliforms and thermotolerant considerably less / Doutor

Wastewater reuse, reclamation and recycling may provide beneficial strategies to manage limited water resources. However, insufficient treatment of municipal wastewater poses potential risk to environmental and public health regarding incidences of viral pathogens. The reduction of pathogenic microorganisms is essential to minimize human health risk associated with the reuse of wastewater. The United States Environmental Protection Agency is reviewing the use of coliphages as a potential indicator organism of fecal contamination in recreational waters. Coliphages are viruses than infect enteric coliform bacteria, and are consistently present in domestic wastewaters. They are similar in size and shape to human enteric viruses, and are more resistant to removal by disinfection than enteric bacteria. As such, they have long been proposed as indicators of fecal pollution. However, traditional bacterial indicators (i.e. Escherichia coli) are not reliable indicators for viral pathogens. Monitoring viral pathogens and utilizing the most sufficient wastewater treatment technologies are necessary to minimize public health risk associated with exposure. It is therefore of interest to better understand the removal of coliphages by sewage treatment processes.

This research has primarily been concerned with the study of the kinetics, design and operation of completely mixed aerated lagoons. Throughout the experimental research laboratory-size completely mixed aerated lagoons, composite synthetic substrate and mixed biological culture were used.

A microwave enhanced advanced oxidation process using hydrogen peroxide (MW/H₂O₂-AOP) was used for the release of nutrients and the destruction of solids from secondary municipal sewage sludge. The significant factors affecting the MW/H₂O₂-AOP that would yield maximum soluble substrates were studied. Using a computer statistical software package for experimental design and data analysis, four factors including microwave heating temperature, heating time, hydrogen peroxide dosage, and sludge solids content, were selected and examined. The initial sludge TS content and hydrogen peroxide dosage were the most significant factors for the solubilization of COD and nutrients release under the experimental conditions selected in this study. Overall, the maximum solubilization of nutrients was obtained at 2.5 % of total solids content, 2% of hydrogen peroxide by weight, 5 min. of microwave heating and 120 ºC. The effects of combination of microwave treatment and oxidative reagents on solids destruction and nutrients release were also investigated. Microwave enhanced advanced oxidation processes (MW-AOP), such as MW/O₃, MW/H₂O₂ and MW/H₂O₂/O₃, were conducted at 100 °C. In terms of nutrients release and solids reduction, the MW/H₂O₂/O₃-AOP yielded the best result. Subsequently, three factors including microwave heating temperature, hydrogen peroxide dosage, and ozone dosage, were investigated. The best result, in terms of the release of phosphate and ammonia, and solids reduction, was obtained with additions of 2 % hydrogen peroxide by weight and ozone dosage of 5.09 mg/ml, and operating at 120ºC. About 95%, 32% and 78% of TP, TKN and COD were released into the solution, respectively. The microwave enhanced advanced oxidation processes, with and without an addition of ferrous sulfate (MW/H₂O₂-AOP and MW/H₂O₂/Fe+²-AOP), were also studied for reducing solids, and solubilizing nutrients from the secondary sewage sludge. For the MW/H₂O₂/Fe+²-AOP, the best results of solubilization, in terms of orthophosphate, ammonia and soluble chemical oxygen demand, were obtained at treatment temperatures of 40 ºC, the yields decreased as the temperature was increased. The highest yields of solubilization were obtained at 60 ºC for orthophosphate, and at 80 ºC for both ammonia and soluble chemical oxygen demand. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate

No description available.

Industrial wastewater treatment using conventional treatment technologies is becoming challenging day-by-day due to presence of ‘newer’ refractory compounds, lower treatment efficiencies and stricter environmental laws. Combination of conventional treatment techniques with modern treatment technologies like membrane filtration or advanced oxidation processes (AOPs) has shown promise in achieving high efficiencies. In this work we have worked towards development of a membrane nanofiltration unit to treat coagulation-flocculation pretreated IWW from a specialized treatment facility. More specifically, state-of-the-art TiO2 ceramic NF membranes with low molecular weight cut off (MWCO) (200, 450, 750, 8500 Da) purchased from Inopor Gmbh were tested on 6 different IWW samples due to their superior chemical stability, higher flux and high fouling resistance along with 3 commercial polymer NF membranes (NF90, NFX, NFS) for comparison purposes. Additionally, wastewater characterization dataset including composition analysis using Gas-chromatography Mass-spectroscopy (GC-MS) is leveraged to build data driven models for membrane performance prediction. ‘200 Da’ ceramic NF membrane was able to reject significant COD with an average rejection of 77% and 60% for two IWW samples with permeate flux between 5-15 LMH at 100-120 psi trans-membrane pressure (TMP). ‘200-Da’ membrane was also found to achieve more flux than ‘450 Da’ membrane while rejecting more COD at the same time. ‘200 Da’ membrane also showed lower flux decline than polymer membranes. Additionally, the ceramic NF membranes were found to be easily chemically cleanable restoring wastewater flux after fouling. Since polymer NF membranes were found to reject at higher COD rejection efficiencies (60-90%) and permeate flux, further improvement in ceramic membranes is needed to treat at higher efficiencies. 200 Da, NF90 and NFX membranes were found to be promising to reduce COD below target (600 mg/L) and should be studied further for this application. / Thesis / Master of Applied Science (MASc) / Conventional technologies for Industrial wastewater (IWW) treatment include biological treatment, coagulation, flocculation, adsorption and filtration. Many industries produce IWW with high concentration of biologically toxic organics ruling out the option of biological treatment. Moreover, with stricter regulatory laws in place for effluent discharge, adoption of new treatment technologies is needed. Nanofiltration (NF) is one such treatment technology that has seen a lot of growth in the past decade since its advent in 1980s. Polymer nanofiltration has been successfully used in applications such as dye removal in textile industry, as a pre-treatment method in desalination plants, for organic solvent nanofiltration in pharmaceutical industry and many more. More recent development of ceramic nanofiltration membranes has seen a lot of interest from researchers around the world due to their superior physical and chemical robustness, fouling resistant properties and higher permeability as compared to polymer NF membranes, though only a small amount of ceramic NF membranes are applied in industrial projects. To this end, we have conducted laboratory scale testing of 4 state of the art ceramic NF membranes on multiple real industrial wastewater samples collected from a specialized IWW treatment plant, along with 3 polymer NF membranes for comparison purposes. Additionally, a data-driven modeling approach leveraging the wastewater composition dataset is shown. The models can be used to predict % rejection of an unseen compound based on its chemical properties and provide insights into complex interactions between compounds and the membrane.

To effectively operate and manage the complex wastewater treatment system, simplified representations, known as wastewater modeling, are critical. Wastewater modeling allows for the understanding, monitoring, and prediction of wastewater treatment processes by capturing intricate relationships within the system. Process-driven models (PDMs), which rely on a set of interconnected hypotheses and assumptions, are commonly used to capture the physical, chemical, and biological mechanisms of wastewater treatment. More recently, with the development of advanced algorithms and sensor techniques, data-driven models (DDMs) that are based on analyzing the data about a system, specifically finding relationships between the system state variables without relying on explicit knowledge of the system, have emerged as a complementary alternative. However, both PDMs and DDMs suffer from their limitations. For example, uncertainties of PDMs can arise from imprecise calibration of empirical parameters and natural process variability. Applications of DDMs are limited to certain objectives because of a lack of high-quality dataset and struggling to capture changing relationship. Therefore, this dissertation aims to enhance the stable operation and effective management of WWTPs by addressing these limitations through the pursuit of three objectives: (1) investigating an efficient data-driven approach for uncertainty analysis of process-driven secondary settling tank models; (2) developing data-driven models that can leverage sparse and imbalanced data for the prediction of emerging contaminant removal; (3) exploring an advanced data-driven model for influent flow rate predictions during the COVID-19 emergency. / Thesis / Doctor of Philosophy (PhD) / Ensuring appropriate treatment and recycling of wastewater is vital to sustain life. Wastewater treatment plants (WWTPs), which have complicated processes that include several intricate physical, chemical, and biological procedures, play a significant role in the water recycling. Due to stricter regulations and complex wastewater composition, the wastewater treatment system has become increasingly complex. Therefore, it is crucial to use simplified versions of the system, known as wastewater modeling, to effectively operate and manage the complex system. The aim of this thesis is to develop data-driven approaches for wastewater modeling.

No description available.

The treatment of municipal, industrial and agricultural wastewater produces a semi-liquid mixture known as sludge. The costs associated with pumping, transporting, treating, storing, and disposing of sludge are significant. Therefore, sludge dewatering techniques are employed to increase the solids content of the material by separating the solid and liquid components, thus reducing the overall volume requiring further handling. Non-mechanical dewatering methods require large areas of land and favorable climatic conditions, while mechanical dewatering technologies require significant capital investment and ongoing operation and maintenance by highly trained personnel. Due to these shortcomings, the conventional methods of sludge dewatering are not applicable to scenarios where: the quantity of sludge is small, there is limited budget, there are land restrictions, or dewatering is performed seasonally. An alternative approach that has recently attracted considerable attention is the use of dewatering fabrics; specially engineered textiles supplied in the form of very large bags into which the sludge is pumped. The concept itself is simple, pressure inside the bag pushes the free water through the fabric while the solid material is retained within. Unfortunately, these products have exhibited poor dewatering performance for certain feed materials. In this work, a series of ‘next-generation’ engineered dewatering fabrics featuring elongated ‘slit’ pores were produced using laser cutting techniques. A comprehensive analysis of the effect of the filter properties on dewatering performance was performed using sludge sourced from two different operations: municipal wastewater treatment and precious metal mining. / Thesis / Master of Applied Science (MASc) / In recent years, the use of engineered dewatering fabrics has emerged as a viable alternative to conventional methods of sludge dewatering in numerous application areas including municipal wastewater, mining, and pulp and paper. Previous studies have focused on the development of empirical ratios between dewatering performance and the porous properties of the textile material. The limitation of this approach is that the latter is difficult to characterize using currently available techniques due to the complex, nonuniform pore structure of conventional woven and nonwoven dewatering fabrics. In this study, a series of dewatering fabrics were produced using advanced microfabrication techniques featuring well-defined slit-pore geometries. Full-factorial design-of-experiment frameworks were employed to evaluate the effects of slit-pore dimensions and slit-pore spacing on cake layer development and key dewatering performance metrics. Laboratory scale dewatering performance tests were performed using both anaerobic digested sludge from the Woodward Avenue Wastewater Treatment Plant in Hamilton, Ontario and metal precipitate sludge from a nickel-copper mine in Ontario, Canada. The results from this study provide new insights into the importance of the cake layer in geotextile dewatering and the impact of pore geometry, porosity, and polymer performance on cake layer development.