PhD, University of Cincinnati, 1999, Engineering : Environmental Engineering

Increasing regulatory pressure for VOC emissions reduction has accelerated the development of more cost effective VOC air pollution control (APC) technologies. Biofiltration is a viable technology to fill this role, for the purification of air streams polluted with biodegradable VOCs. In the biofilter, these pollutants diffuse from the air stream into a stationary mass of moist biological film, where they are oxidized by enzymatic catalysis at ambient pressures and temperatures. Properly operated, this natural, biological mineralization process will produce only benign by-products, such as inorganic salts, carbon dioxide, and water, with some additional biomass. Although research into the science and development of the technology of biofiltration has been performed for over fifteen years, biofiltration remains not widely accepted as a proven technology for VOC APC. This perception is especially true for applications treating high influent VOC concentrations and requiring high VOC removal efficiencies. This research was undertaken to develop a new, cost effective biofiltration technology which can reliably treat air streams polluted with high VOC concentrations and achieve very high removal (elimination) efficiencies. Investigations were made to evaluate different biological attachment media, in order to identify the medium most suited to such an application. Using this medium, a reliable biofiltration technology was developed and extensively tested, which can achieve the goal of reliably treating high concentrations of VOCs at high loadings with high removal efficiency. Techniques for the management and control of the accumulating by-product biomass were developed. Procedures are presented for the calculation of VOC solubility and biological kinetic parameters, at the biofiltration operating temperature. A procedure for estimating the upper limit for biofiltration for the influent air VOC concentrations is presented. A simple, explicit biofilter design equation was (open full item for complete abstract)

Committee: Makram Suidan (Advisor) Subjects:

MS, University of Cincinnati, 2019, Engineering and Applied Science: Environmental Engineering

Traditionally, volatile organic compounds (VOCs) are treated by physicochemical processes such as adsorption by activated carbon, oxidation by a thermal internal combustion engine, and catalytic oxidation. Such mechanisms have successfully reported very high removal efficiencies, but cost efficiency is at stagnation levels, carbon foot-prints are in increasing rates, and energy consumption is elevating due to the excessive off-gases emissions. Environmental biotechnologies represent cost-efficient and environmental friendly processes for air pollution control. However, several challenges face biological treatment processes such as variability of flow rate, composition of contaminants in waste streams, and the long-term operation stability. Since industry looks to develop cost-effective and eco-friendly processes to comply with the 1990 Amendments of the Clean Air Act, biological systems are becoming more suitable in eliminating biodegradable VOCs. Biological systems are also suitable for treating large volumes of gaseous waste streams that contain low concentrations of biodegradable contaminants. It is also worthwhile noting that several developments have been applied to the conventional biofiltration process to adapt more widely with the various composition of VOCs such as recalcitrant chemicals often found in several off-gases emissions. The objective of this study is focused on enhancing the bioavailability and eventually biodegradation of a very hydrophobic compound in a fungi-cultured trickle bed air biofilter (TBAB) by applying a number of operational techniques, starvation, and investigating the concept of introducing bio-additives (cell-filtrate) as a means for allowing consistency of biomass along the length of the biofilter. Emphasis is being placed on the impact of biosurfactants which are known to enhance the solubility of recalcitrant compounds to biological treatment. Two VOCs (2-ethylhexanol (2-EH), a hydrophobic VOC and methoxy-2-propanol (M2P), (open full item for complete abstract)

Committee: George Sorial Ph.D. (Committee Chair); Margaret Kupferle Ph.D. (Committee Member); Drew McAvoy Ph.D. (Committee Member) Subjects: Environmental Engineering

Doctor of Philosophy, The Ohio State University, 2017, Food, Agricultural and Biological Engineering

Solid-state anaerobic digestion (SS-AD) can be used to convert abundant, low moisture feedstocks, such as switchgrass, to methane (CH4)-rich biogas. However, biogas is a gas under ambient conditions, and impurities need to be removed before it can be upgraded to other products. Integration of SS-AD with biological conversion of biogas to methanol could provide an environmentally friendly method to convert renewable feedstocks to liquid chemicals. The first project showed that limited air exposure had a minimal effect on SS-AD of switchgrass, and thermophilic conditions (55°C) improved biogas yields (102–145 L CH4 kg VSadded-1) compared to mesophilic (37°C) (88–113 L CH4 kg VSadded-1). Net energy analysis of a theoretical “garage-type” SS-AD reactor suggested that positive net energy could be obtained at elevated total solids contents (= 20% TS). A new methanotroph strain (Methylocaldum sp. 14B) was isolated from the digestate of a mesophilic SS-AD reactor. Strain 14B successfully converted biogas to methanol using phosphate as a methanol dehydrogenase (MDH) inhibitor and formate as an electron donor. The maximum methanol concentration (0.43±0.0 g/L) and CH4 to methanol conversion ratio (25.5±1.8%) were obtained using strain 14B suspended in NMS medium containing 50 mM phosphate and 80 mM formate a biogas:air ratio of 1:2.5 (v/v). Abiotic gas-liquid mass transport of O2 in a trickle-bed reactor (TBR) packed with ceramic balls was two times higher than an unpacked TBR. The results suggested that the TBR enhanced gas oxidation compared to shake flasks. Maximum methanol productivity (0.9 g/L/d) in the non-sterile TBR was obtained at 12 mmol formate and 3.6 mmol phosphate and a biogas:air ratio of 1:2.5. Operation under non-sterile conditions impacted the microbial community of the TBR. A mathematical model that considered mass transport and gas consumption kinetics was used to generate results that were similar to selected semi-batch data from the lab-s (open full item for complete abstract)

Committee: Jay Martin PhD (Advisor); Gonul Kaletunc PhD (Committee Member); Ajay Shah PhD (Committee Member); Zhongtang Yu PhD (Committee Member) Subjects: Agricultural Engineering; Alternative Energy; Environmental Science

Doctor of Philosophy, The Ohio State University, 2017, Public Policy and Management

Recent studies on empowerment in public administration have shown many benefits of employee empowerment, including higher job satisfaction, organizational commitment, innovative behavior, and perception of workgroup performance (Fernandez & Moldogaziev, 2011, 2013a, 2013b). However, empowerment's potential contributions to individual and organizational performance remain largely unexplored. The few studies that have examined the connection between employee empowerment and performance outcomes relied on self-reported measures, which are unreliable and inaccurate (Meier & O'Toole, 2013). Moreover, these studies do not provide much insight about the underlying processes through which empowerment from the top of an organization may trickle down to the bottom of the organization. The present study fills these gaps by examining the direct and indirect effects of empowering managerial practices on attitudes, behaviors, and performance of employees at both the individual and workgroup levels. The main research question of this study is: does empowerment lead to higher employee and organization performance in public agencies? To address this question, the study develops a cascading or “trickle-down” model of empowering leadership, in which senior managers' empowering managerial practices are expected to influence junior managers' empowerment practices, which, in turn, are expected to affect frontline employees' work behaviors. More specifically, this study first examines how senior managers' empowering leadership practices affects junior managers' feelings of being empowered and their use of empowering practices toward their direct reports. Second, this study examines the association of junior managers' empowering leadership practices with performance outcomes at different levels. These effects are evaluated in relation to employee effectiveness (i.e., task performance, conscientiousness, and voice), workgroup effectiveness (unit-level task performance, conscientiousness, (open full item for complete abstract)

Committee: Shahidul Hassan (Advisor); Jos C.N. Raadschelders (Committee Member); Mary Tschirhart (Committee Member) Subjects: Organismal Biology; Public Administration

MS, University of Cincinnati, 2016, Engineering and Applied Science: Environmental Engineering

This dissertation includes a detailed review on the application of two different biofiltration systems, 1. Classical biofilters and 2. Biotrickling filters, for the removal of various air pollutants. The biofiltration of volatile organic compounds, fuel emissions, biogas, off gases and malodorous gases are studied in detail. The removal mechanisms including aerobic and anaerobic processes involved in the breakdown of the gas phase contaminants within natural and synthetic biofiltration units are studied. This is followed by an experimental evaluation of the performance of a controlled trickle bed air biofilter (TBAB) for the removal of chloroform. Chloroform is a higher chlorinated methane and a highly volatile compound. It is directly emitted into the atmosphere through several industrial sources such as pharmaceutical, pulp and paper industries. It is also formed as a byproduct of chlorination disinfection in water and wastewater sources and subsequently volatilized into the atmosphere. Chloroform, also known as trichloromethane, contains three chlorine atoms making it very recalcitrant and stable in the environment. It is also a highly hydrophobic compound making it an extremely difficult candidate for biodegradation. In this study, this challenge is overcome by evaluating the biodegradation potential of chloroform in the presence of a cometabolite, ethanol, and using filamentous fungi as the principle biodegrading consortium within the TBAB. The TBAB receives chloroform and ethanol in its gas phase and enriching nutrients in a buffered liquid phase. Chloroform and Ethanol were supplied at different feed ratios including 1:5, 1:10, 1:20, 1:30, 1:40 with ethanol concentrations ranging from 25 to 200 ppmv. A removal efficiency of 80.9% was observed when treating 5 ppmv of chloroform with 200 ppmv of ethanol and an elimination capacity of 0.238 g/m³.h was achieved. The study further extends to the determination of the removal kinetics for chloroform and q (open full item for complete abstract)

Committee: George Sorial Ph.D. (Committee Chair); Soryong Chae Ph.D. (Committee Member); E Sahle-Demessie Ph.D. (Committee Member) Subjects: Environmental Engineering

PhD, University of Cincinnati, 2013, Engineering and Applied Science: Environmental Engineering

Biofiltration systems demonstrated to very effective in removal of volatile organic compounds (VOCs) from air operating under dynamic loading rates and stressed conditions. More interestingly, Trickle Bed Air Biofilters (TBABs) offer more optimal and controllable operations which result in low maintenance costs over traditional biofilters. Furthermore, due to their higher removal efficiency, consistent performance, and harmless by-products generated they became an attractive option for controlling VOCs emissions from various industrial processes. Yet, biofiltration systems face a number of challenges to compete new proposed techniques such as two-phase bioreactors and oil emended biofilters. Characteristically, hydrophobic compounds, with higher Henry's law constant, present a great challenge for these systems as they are not soluble in water. Limited bioavailability of these VOCs could trigger mass transfer to be rate limiting from gas to liquid phase and hence negatively affecting biofilters performances. Moreover, as biofilters are biologically dependent systems, the exact characterization of the microbial community structures within the active biomass need to be developed in order to get deep insight of the species involved to make the biofiltration technique more efficient, reliable, and oriented either to specific VOCs as well as to be flexible in handling a variety of VOCs. Most importantly, air emissions are always mixture of different type of gases rather than a sole VOC. Hence, inhibitory effect among VOCs could hinder the widespread application of these systems in facilities where off gases are a combination of hydrophilic and hydrophobic VOCs. Finally, variability in waste gases flow and fluctuations in their concentrations limit the treatment efficiency of the biofiltration systems. In this regard, the current study investigated several techniques to effectively biodegrade hydrophobic contaminants. Responding to this aim, the solutions presented (open full item for complete abstract)

Committee: George Sorial Ph.D. (Committee Chair); Ashraf Aly Hassan Ph.D. (Committee Member); E Sahle-Demessie Ph.D. (Committee Member); Makram Suidan Ph.D. (Committee Member); David Wendell Ph.D. (Committee Member) Subjects: Environmental Engineering

PhD, University of Cincinnati, 2010, Engineering and Applied Science: Environmental Engineering

Biological treatment represents low-cost and environmental friendly option for air pollution as compared to incineration, catalytic oxidation and adsorption. It has several advantages like minimal power consumption, few byproducts and cost effectiveness. However, several challenges face biological treatment processes such as variability of flow rate and composition of contaminants in waste streams. Furthermore, hydrophobic compounds are not readily available for the microorganisms, creating a deficiency for the use of biological treatment in the industry. Biofiltration for VOCs control is best operated at steady loads of hydrophilic VOCs. In practice the existence of hydrophobic compounds in waste streams is inevitable. In addition, variations in contaminant loads are common in real applications. The objectives of this study are to introduce biological treatment as an effective technique for non-methane hydrocarbon removal from air under stressed operating conditions. Emphasis is being placed on hydrophobic compounds which are known to be recalcitrant to biological treatment. Two hydrophobic compounds; n-hexane and benzene, which are carcinogenic and toxic, were utilized as model compounds. Both compounds were studied separately under different operating conditions. Loading rates up to 48 and 77 g/(m3 h) for n-hexane and benzene were applied at the inlet prividing elimination capacities of 39 and 61 g/(m3 h) , respectively. These elevated elimination capacities have not been achieved by any reported research for hydrophobic compounds at practical removal efficiencies as obtained in this study (minimum 78%). Surfactants were introduced in the biofiltration system as means for enhancing solubility. The effect of two different surfactants; Triton X-100 and Tomadol 25-7, were investigated at different loading rates for the biodegradation of n-hexane operating under neutral pH. Other means of increasing the bioavailability of hydrophobic compounds was the introduction o (open full item for complete abstract)

Committee: George Sorial PhD (Committee Chair); Margaret Kupferle PhD, PE (Committee Member); Paul Bishop PhD (Committee Member); E Sahle-Demissie PHD (Committee Member) Subjects: Environmental Engineering

PhD, University of Cincinnati, 2007, Engineering : Chemical Engineering

The first part of this thesis encompasses fundamental studies on the attachment and growth of biofilms onto synthetic non adsorbing, macroporous solid foams aiming at supporting bioactive microorganisms in the removal of intricate hydrogen sulfide polluted airstreams in trickle bed columns at negligible pressure drop. A new theoretical model that predicts the performance of biofilters packed with non adsorbing, macroporous media was simultaneously developed based in the distribution of the fouled airstream within the porous media and around it, so that the geometric properties of the packing media can be chosen as to maximize the amount of air passing within the media where most microorganisms are located. During the experimental phase of this study, colonization of such non adsorbing, macroporous media with microorganisms was enhanced by the addition of positively charged, polymeric coatings which increase the attachment and spreading of the biofilms due to cell binding and electrostatic charge cancellation at physiological pH. Impedimetric tests using golden microelectrodes were applied separately to corroborate such results, and other cofactors reported in the Literature for the attachment of animal cells onto plastic surfaces were tested with the methodology. The use of such cofactors for biofilm attachment purposes and the impedimetric tests for the determination of the kinetics of the biofilm morphology development based in the transient change of observables such as resistance and capacitance, are the first attempts on such approaches to date. In the second part of this thesis, the macroporous, non adsorbing foams were replaced by adsorbing, reactive units of similar geometric properties but containing iron (III) (oxy)(hydr)oxides operating as adsorption towers and trickle bed biofilters. The abiotic H2S removal capability of such iron bearing media was found to be enhanced by dripping water down the bed, which allowed for complete elimination of the sulfide (open full item for complete abstract)

Committee: Dr. Rakesh Govind (Advisor) Subjects:

Master of Arts, University of Toledo, 2011, Philosophy

Liberalism has failed. The paradox in modern society between capitalism and democracy has violated the very principles of liberty, equality, and social justice that liberalism bases its ideology behind. Liberalism, in directly choosing capitalism and private property has undermined its own values and ensured that the theoretical justice, in which its foundation is built upon, will never be. This piece of work will take the monumental, landmark, liberal work, A Theory of Justice, by John Rawls, as its foundation to examine the contradictory and self-defeating ideological commitment to both capitalism and democracy in liberalism. I will argue that this commitment to both ideals creates an impossibility of justice, which is at the heart of, and is the driving force behind liberal theory. In liberalism‟s place, I will argue that Pierre-Joseph Proudhon‟s anarchism, as outlined in, Property is Theft, offers an actual ideological model to achieving the principles which liberalism has set out to achieve, through an adequate and functioning model of justice.

Committee: Benjamin Pryor Dr. (Committee Chair); Ammon Allred Dr. (Committee Member); Charles Blatz Dr. (Committee Member) Subjects: Philosophy

Doctor of Philosophy in Urban Studies and Public Affairs, Cleveland State University, 2009, Levin College of Urban Affairs

The Republic of Korea's efforts to accelerate the development of its economy in the aftermath of an extremely destructive civil war led to the concentration of capital and activity in areas that resemble the growth poles described by Perroux (1950) and Hirschman (1958). These poles led to an extreme centralization of economic activity and people in the Seoul Metropolitan Area (SMA). More than 48 percent of the GDP, 90 percent of the headquarters of major firms, and 48 percent of the population is concentrated in 11.8 percent of the Republic's land (2006 figures). Despite the agglomeration economies, the national government has investigated policies and practices to spatially reorganize the growth-pole regions' industrial base to bring more balanced growth to other parts of the country. These efforts have been mostly unsuccessful. To better understand factors that could be undermining efforts to decentralize and enhance the distribution of economic activity this study looks at the relationship between social linkages among power elites and the concentration of economic activity. After assessing the existence of growth poles and their dominance, this study also analyzes the consequences of the concentration of capital into two regions. The third and main part of the study uses social network analysis (SNA) to identify the existence of a powerful social system that sustains these growth-pole regions and impede meaningful change. The data analysis strongly suggests that changes in the ‘creative destruction' of social patterns at a minimum must occur at the same time that efforts are made to alter path-dependent economic patterns. The final section of the dissertation presents some recommendations to achieve the needed reforms in social networks that must precede any change in the concentration of economic activity.

Committee: Mark Rosentraub PhD (Committee Chair); William Bowen PhD (Other); Harlow-Rosentraub Karen PhD (Other); Lee Sugie PhD (Other) Subjects: Area Planning and Development; Economic Theory; Geography; Public Administration; Social Structure; Sociology; Urban Planning

Doctor of Philosophy, Case Western Reserve University, 2006, Mechanical Engineering

Experimental results on flow pattern transitions, pressure drop and flow characteristics for cocurrent gas-liquid flow through packed bed reactors in microgravity is presented and analyzed. The pulse flow regime is shown to exist over a much wider range of gas and liquid flow rates when under microgravity conditions. A new model is developed to predict the transition from bubble flow to pulse flow based on the dimensionless Suratman number. The Suratman number is shown to represent the balance of forces at the pore level which determine the conditions necessary for the onset of pulse flow in the column. This model is then extended to normal gravity flows in the downward direction for fixed Bond numbers. A model to predict pressure drop in the absence of gravity is also presented. An additional pressure drop term is developed to extend the applicability of the Ergun equation to gas-liquid flow. This term represents the losses resulting from the dynamic interaction between the two phases and is superposed with the liquid viscous and inertia terms to represent the total pressure loss through a reactor bed in a microgravity environment. The modified two-phase Ergun equation is shown to provide good agreement with the experimental results.

Committee: Yasuhiro Kamotani (Advisor) Subjects: