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 …

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 …

Bridging Thermochemical And Biochemical Conversion: Impact Of Biochar Addition On The Anaerobic Digestion Of Aqueous Pyrolysis Condensate, Neha Batta

Electronic Thesis and Dissertation Repository

Profitable treatment of low value waste biomass is one of the biggest challenges of the industry. Where most of the current treatment strategies, such as pyrolysis, are efficient in complete breakdown of hard to synthesize, low value waste biomass such as lignocellulosic wastes, it leads to the generation of secondary waste thereby compromising its efficiency. The aim of this research is to utilize the aqueous pyrolysis condensate as a feedstock for anaerobic digestion, previously adapting the microbial consortia to the acidity and other potential organic inhibitors present in the APC, to produce energy in the form of biogas following the …

Biohydrogen And Biomethane Production From Lignocellulosic Biomass, Chinaza Okeoghene Akobi

Electronic Thesis and Dissertation Repository

The main purpose of this study was to investigate the impact of furfural on mixed cultures during fermentative hydrogen production from lignocellulosic biomass. Small batch studies using synthetic lignocellulosic hydrolysate grown on mesophilic mixed cultures, revealed a threshold furfural concentration of greater than 1 g/L with enhancement to the yields (from the control) observed at 0.5 g/L furfural (at initial substrate-to–biomass (S°/X°) ratios of 0.5 and 1 gCOD/gVSS) and at both 0.5 g/L and 1 g/L furfural (at S°/X° of 2 and 4 gCOD/gVSS). This study was scaled-up from 200 mL to 11 L working volume batches, using half the …

Enhancement Of Biohydrogen Production From Co-Fermentation Of Glucose, Starch, And Cellulose, Medhavi Gupta

Electronic Thesis and Dissertation Repository

The aim of this study was to assess the synergistic effects of co-fermentation of glucose, starch, and cellulose using anaerobic digester sludge (ADS) on the biohydrogen (H₂) production and the associated microbial communities. At initial pH of 5.5 and mesophilic temperature of 37 ºC, the H₂ yields were greater by an average of 27 ± 4% in all the different co-substrate conditions compared to the mono-substrate conditions, which affirmed that co-fermentation of different substrates improved the hydrogen potential. The sensitivity of mesophilic ADS to a temperature shock was also investigated. Unacclimatized mesophilic ADS responded well to a …

Investigation Of Bio-Hydrogen And Bio-Methane Production From Thin Stillage, Noha El-Sayed Nasr

Electronic Thesis and Dissertation Repository

An evaluation of single-stage and two-stage anaerobic digestion processes for biomethane and biohydrogen production using thin stillage was performed to assess the viability of biohydrogen production from thin stillage and the impact of separating the acidogenic and methanogenic stages on anaerobic digestion with hydrogen production in the first stage. A comparative evaluation of anaerobic digester sludge (ADS) and acclimatized anaerobic digester sludge (AADS) for biohydrogen production was performed at various S°/X° ratios. The optimum range of S°/X° ratio for hydrogen production was found to be 1 to 2 gCOD/gVSS using conventional ADS and 3 to 6 gCOD/gVSS using AADS. Maximum …

Enhancement Of Biohydrogen And Biomethane Production From Wastes Using Ultrasonication, Elsayed Elrefaey Elbeshbishy

Electronic Thesis and Dissertation Repository

This thesis demonstrated the feasibility of using ultrasonication to solubilize the particulate matter, suppress the growth of methanogens, and enrich the biohydrogen producers, thus overcoming the main challenge of biohydrogen systems i.e. long-term stability and contamination with methanogens. Furthermore, this work emphasized the benefits of applying ultrasonication inside a bioreactor over using it as a pretreatment for biohydrogen and biomethane production from wastes. The results of this work showed that sonicating hog manure at specific energy (SE) of 500 kJ/kg TS resulted in a 20% increase in methane production and 36% increase in VSS destruction. The viability of using ultrasonication …

The Effect Of Particle Size On Hydrolysis And Modeling Of Anaerobic Digestion, Saad Aldin

Electronic Thesis and Dissertation Repository

Batch experiments were performed to investigate the effect of particulate protein particle size on the hydrolysis of casein in anaerobic degradation. While particle size did not affect the ultimate protein degradation efficiency, the hydrolysis rate coefficient increased from 0.034 to 0.298 d-1 with the change in specific surface area from 0.01 to 0.192 m2/g. The maximum methane production rate was affected by the particle size change, although the ultimate amount of methane produced was approximately the same despite the change in specific surface area. A mathematical relationship between the hydrolysis rate coefficient and specific surface area was developed and a …