Engineering Commons^™

Catalytic And Non-Catalytic Methods For Hydrocarbon Upgrading, Valorization, And Pollutant Control, Michael Morgan Royko

Theses and Dissertations

This work investigates catalytic and non-catalytic oxidative chemical upgrading and pollutant remediation techniques to responsibly utilize hydrocarbon feedstocks with existing infrastructure as the transition to more renewable and cleaner feedstocks for energy generation are developed. These technologies include oxidative dehydrogenation of ethane, development of magnetically separable catalysts to reduce carbon monoxide emissions during biomass upgrading as well as the subsequent use of the upgraded biomass for partial coal replacement, and electrochemical treatment of a washcoat free wire mesh supported catalyst to reduce carbon monoxide emissions in combustion exhaust.

First, doping of secondary metals in M1/M2 catalysts for oxidative dehydrogenation of …

Torrefaction Of Mixed Solid Waste, Zhuo Xu

Dissertations, Master's Theses and Master's Reports

The world is witnessing unprecedented accumulation of solid wastes in the environment and landfills with well-documented ecological, environmental, health, and economic consequences. With population growth and rise in living standards, solid wastes generation will increase, making the issue more pressing. In addition, current practices of solid waste disposal are creating an immediate challenge and a long-term disaster-scale problem. The solid wastes comprises two main groups of materials: (i) fiber wastes (paper, food, wood, trimming, 61% of U.S. municipal solid waste) and (ii)uniquely challenging subset of plastic wastes (13%) that become a threat to global sustainability including dangers to marine and …

Paddle Mixer-Extrusion Reactor For Torrefaction And Pyrolysis, Stas Zinchik

Dissertations, Master's Theses and Master's Reports

This work is focused on the fundamental understanding and the development of paddle mixer reactors (or modified screw augers). This work will contribute to the effort of the thermal conversion of biomass and wastes. We developed and studied two paddle systems (i) 25-mm lab-scale (up to 1 kg/hr) and (ii) 101-mm pilot-scale (up to 100 kg/hr). Thermal behavior of the two systems was studied and it was estimated that the lab-scale system has a high heating rate of up to 530 °C/s. Residence times were thoroughly measured and were determined as a function of rotation frequency and volume fraction. We …

A Quantitative Environmental Assessment Of Incorporating Torrefaction Into Farming Enterprises In Eastern South Dakota, Dinesh Fuyal

Electronic Theses and Dissertations

The use of renewable energy sources has been increasing in the recent years due to population growth and environmental concerns. Biomass is a promising energy source that can be used to produce biofuels or torrefied pellets. Torrefied biomass may be used in power plants, industrial and residential heating, feedstocks for gasification, air and water filtrating, and soil amendment. The interest of torrefied pellets as energy sources for various applications has been increased in the recent years due to the concerns about energy security and environmental issues. This study focuses on the economic and environmental assessment of agricultural feedstocks like corn …

Techno-Economic And Life Cycle Assessments Of Biofuel Production From Woody Biomass Through Torrefaction-Fast Pyrolysis And Catalytic Upgrading, Olumide Winjobi

Dissertations, Master's Theses and Master's Reports

Biofuel production through fast pyrolysis of biomass is a promising conversion route in the production of biofuels compatible with existing technology. The bio-oil produced from fast pyrolysis is a versatile feedstock that can be used as a heating oil or upgraded to a transportation hydrocarbon biofuel. Comparative study of a one-step, fast pyrolysis only pathway and a two-step torrefaction-fast pyrolysis pathway was carried out to evaluate the effect of torrefcation on (i) the minimum selling price of biofuel and (ii) the potential life cycle GHG emissions of the biofuel production pathway.

To produce bio-oil which can serve as a substitute …

Techno-Economic Feasibility Of Distributed Torrefaction Systems Using Corn Stover Feedstock, Evan Almberg

Electronic Theses and Dissertations

This study investigated the economic feasibility of distributed torrefaction biorefining systems using corn stover feedstock to generate value-­‐added products. Distributed torrefaction systems have the potential to operate on private agricultural enterprises as well as community-­‐scale processing facilities, similar in scale to local grain elevators. Distributed systems will thus, reduce the need for large capital investments for dedicated commercial biorefining facilities and decrease logistical concerns for harvesting and marketing the torrefied corn stover products. In this study, a techno-­‐economic model was developed to analyze the economics of harvesting techniques, logistics, processing requirements, and end product utilization. Results were determined using baseline …

Modeling Of Biomass Torrefaction And Pyrolysis And Its Applications, Jordan L. Klinger

Dissertations, Master's Theses and Master's Reports - Open

Utilizing biomass provides a possible near-term alternative solution for fossil energy dependence in both electricity generation and transportation. Though thermochemical conversion can produce solid/liquid fuels that are compatible in existing infrastructure, detailed scientific chemical and mechanistic understanding are still being developed. In contribution to these efforts, this work is focused on development of a semiempirical, lumped parameter, chemical kinetic model to describe the degradation of woody biomass.

The initial kinetic model was developed in the torrefaction region to describe the gas-phase evolution of products (water, organic acids, permanent gases, and furfural) through a three consecutive reaction model. In this model, …

Production Of Bio-Coal And Activated Carbon From Biomass, Diana C. Cruz

Electronic Thesis and Dissertation Repository

The slow pyrolysis of different biomasses (maple wood, birch bark, switch grass, coffee pulp and corn stalk) was studied with the aim to produce a solid pyrolysis product (bio-coal) with promising properties and potential for use in traditional fossil-coal applications. Batch pyrolysis experiments were conducted in a Mechanically Fluidized Reactor (MFR) at temperatures ranging from 143 to 665 ^oC, which includes the torrefaction temperature range (200-300 ^oC). The effects of temperature and holding time on bio-coal mass yields were determined. The bio-coals were characterized in detail and a highly-controlled study on bio-coal hygroscopicity is presented. Optimal conditions for …