Engineering Commons^™

A Foray Into Laboratory Scale Soil Incubations With Corn Stover And High Lignin Fermentation Byproduct, Michelle Wang

ENGS 88 Honors Thesis (AB Students)

As the production of biofuels increases to meet the demands of a growing low carbon economy, questions of sustainability surrounding its feedstock and waste streams have become increasingly relevant. In the biofuel production process, crop residues like corn stover are harvested from the field and converted to biofuels leaving generating a residue called high lignin fermentation byproduct (HLFB). From extensive process modelling in the literature, it is suggested that HLFB should be either combusted to fuel auxiliary conversion processes or returned to the soil in place of the crop residues that were harvested. Currently, there is little literature testing the …

Development Of Novel Membranes For Nanocarbon Enhanced Separation With Application In Biofuels And Solvent Recover, Oindrila Gupta

Dissertations

Pharmaceutical industries historically have had one of the highest amounts of solvent waste generated per unit of drug manufactured. Energy requirements and carbon footprint of current solvent recycling processes tend to be quite high, and the incineration of the solvents for waste disposal produces toxic air emissions. Also, rapidly increasing demand for energy and strict regulation on engine pollutant emissions have necessitated the use of alcohol as carbon-neutral fuels. Thermal distillation is one of the most common methods for the separation of alcohol-water mixtures. However, its application is limited due to energy requirements and high operating costs, and heating to …

Nutrient Recycling From Aqueous For Nitrogen Supplementation In Algae Growth, Alyssa Young

ELAIA

Algae-derived biofuels have the potential to become a source of renewable liquid fuel via hydrothermal liquefaction. However, for algal biofuels to be economically and environmentally feasible, sustainable nutrient recycling must be achieved. Desmodesmus armatus is a microalga to be used in hydrothermal liquefaction, but it is not yet known if the aqueous product waste from the biofuel production process can be recycled as a nitrogen source to support the growth of subsequent cultures of D. armatus. Here, aqueous product was treated with a Dowex 50WX8 resin for twenty-four hours. Growth media was prepared with treated and untreated aqueous product …

Effects Of Temperature And Antioxidants On The Oxidation Of Biodiesel Derived From Waste Vegetable Oil, Randy L. Maglinao, Torrey J. Wagner, Keegan Duff

Faculty Publications

Biodiesel offers several environmental benefits and improvements to some fuel performance properties, but its poor oxidative stability has been a major concern. Currently, the accepted practice to improve biodiesel oxidative stability is the addition of antioxidants; numerous antioxidants have been studied but their effectiveness in inhibiting biodiesel oxidation is difficult to predict due to variation with resonance stability, solubility, reactivity, and volatility. To improve prediction efforts, this study explored the Rapid Small-Scale Oxidation Test (RSSOT) as a means to investigate how biodiesel oxidation is affected by antioxidant concentration and temperature, and compared its results with the oxidative stability index test. …

Parametric Analysis Of A Solid Oxide Fuel Cell Auxiliary Power Unit Operating On Syngas Produced By Autothermal Reforming Of Hydrocarbon Fuels, Jun Dong, Xinhai Xu, Ben Xu, Shuyang Zhang

Mechanical Engineering Faculty Publications and Presentations

A 1 kWe integrated auxiliary power unit (APU) system consisting of an autothermal reformer and a solid oxide fuel cell (SOFC) unit, as well as balance-of-plant components, was designed and analyzed. A relatively easy-to-approach SOFC model was developed in order to conveniently calculate V-I and P-I curves and the system's net efficiency at different operating conditions. The effects of steam to carbon and oxygen to carbon ratios in the reactants, channel dimensions of the SOFC unit, and hydrocarbon fuel types on the integrated APU system's performance were discussed. Five hydrocarbon fuels including diesel, Jet-A, gasoline, ethanol, and methanol were studied …

Minimizing Environmental Impacts For Hub And Spoke Distribution Network Problems Through The Use Of Multi-Objective Evolutionary Algorithms, Ileana Delgado

Open Access Theses & Dissertations

While transportation is crucial to our economy and our personal lives, as a sector it is also a significant source of greenhouse gas (GHG) emissions. The AASHTO report states, "America's transportation system has served us well, but now faces the challenges of congestion, energy supply, environmental impacts, climate change, and threatens the economic, social, and environmental future of the nation". With respect to the environment, transportation is the most visible aspect of supply chains. Transportation emissions can be reduced by implementing approaches that contribute to GHG emissions reduction, for example, the use of low-carbon fuels, new and improved vehicle technologies, …

Resolving The Policy Paradox: The Case Of Biofuel Production In Ireland, Alan Gilmer, Mark J. Mcgarrity, Vivienne Byers

Articles

Purpose – The purpose of this paper is to determine the status of policy design and policy implementation in the biofuel sector in Ireland. The focus of the work addresses the overarching operational context of the biofuel sector in Ireland and the role of different actors in shaping and resolving inconsistencies in policy outlook and practice. Design/methodology/approach – This study used a qualitative research approach involving a series of semi-structured interviews with members of the relevant sub-groups concerned. This study sought to address two questions – whether current or proposed policy is likely to affect consumption of indigenous biofuel feedstocks …

Comparing Nutrient Recovery Via Rapid (Flash Hydrolysis) And Conventional Hydrothermal Liquefaction Processes For Microalgae Cultivation, Caleb Richard Talbot

Civil & Environmental Engineering Theses & Dissertations

Algal biofuels have the potential to provide a scalable source of renewable fuels in the near future. The high nutrient use in algae cultivation and its recovery and recycling is one of the challenges that may limit the scalability and sustainability of algal biofuels. The present study evaluates the use of Hydrolysate obtained after Flash Hydrolysis (FH) of Scenedesmus at 280 C as a nutrient source for microalgae cultivation. FH Hydrolysate nutrient recycling was compared with low temperature batch Hydrothermal Liquefaction (HTL) nutrient recycling. Oocystis and Scenedesmus were cultivated using Hydrolysate as a partial phosphorous (P) and nitrogen (N) source. …

Water Quality Effects Of Cellulosic Biofuel Crops Grown On Marginal Land, Ruoyu Wang

Ruoyu Wang

Identifying, Monitoring, Quantifying And Converting Algae To Bio-Fuels In Bio-Reactors, Alice C. Jernigan

Graduate Theses and Dissertations

Growing algae as a source for bio-fuels has become an area of interest due to concerns about global warming and the reliability and ecology of the production of fossil fuels. Dried algae harvested from a pilot water quality improvement technology at the Rockaway Wastewater Treatment Facility in New York were examined as a source of carbohydrates and lipids for the production of bio-fuels in bio-reactors. The length of storage time, storage conditions, sugar and lipid extraction processes, and fuel production were studied. The results show that if the algae is stored dry (0.015 g/g algae even after a year in …

Co2 Recycling Using Microalgae For The Production Of Fuels, Michael H. Wilson, John Groppo, Andrew Placido, S. Graham, S. A. Morton Iii, Eduardo Santillan-Jimenez, Aubrey Shea, Mark Crocker, Czarena Crofcheck, Rodney Andrews

Center for Applied Energy Research Faculty and Staff Publications

CO₂ capture and recycle using microalgae was demonstrated at a coal-fired power plant (Duke Energy’s East Bend Station, Kentucky). Using an in-house designed closed loop, vertical tube photobioreactor, Scenedesmus acutus was cultured using flue gas as the CO₂ source. Algae productivity of 39 g/(m² day) in June–July was achieved at significant scale (18,000 L), while average daily productivity slightly in excess of 10 g/(m² day) was demonstrated in the month of December. A protocol for low-cost algae harvesting and dewatering was developed, and the conversion of algal lipids—extracted from the harvested biomass—to diesel-range hydrocarbons via catalytic …

Comparative Efficiency And Driving Range Of Light- And Heavy-Duty Vehicles Powered With Biomass Energy Stored In Liquid Fuels Or Batteries, Mark Laser, Lee R. R. Lynd

Dartmouth Scholarship

This study addresses the question, "When using cellulosic biomass for vehicular transportation, which field-to-wheels pathway is more efficient: that using biofuels or that using bioelectricity?" In considering the question, the level of assumed technological maturity significantly affects the comparison, as does the intended transportation application. Results from the analysis indicate that for light-duty vehicles, over ranges typical in the United States today (e.g., 560-820 miles), field-to-wheels performance is similar, with some scenarios showing biofuel to be more efficient, and others indicating the two pathways to be essentially the same. Over the current range of heavy-duty vehicles, the field-to-wheels efficiency is …

Direct And Indirect Greenhouse Gas Emissions From Biomass Storage: Implications For Life Cycle Assessment Of Biofuels, Isaac Robert Emery

Open Access Dissertations

Ethanol and other biofuels from cellulosic feedstocks are currently the most promising candidates to replace a large fraction of gasoline consumption in the United States and reduce greenhouse gas emissions. Gaps in current approaches to estimating the net greenhouse gas emissions from second-generation biofuels may lead to underestimation of the carbon intensity of these fuels. Current life cycle assessment models of biofuels do not sufficiently account for biomass losses and emissions associated with the harvest and storage of biomass feedstocks, which can require additional fuel and materials use on the farm as well as reducing the effective yield of a …

Review Of Us And Eu Initiatives Toward Development, Demonstration, And Commercialization Of Lignocellulosic Biofuels, Venkatesh Balan, David Chiaramonti, Sandeep Kumar

Civil & Environmental Engineering Faculty Publications

Advanced biofuels produced from lignocellulosic biomass offer an exciting opportunity to produce renewable liquid transportation fuels, biochemicals, and electricity from locally available agriculture and forest residues. The growing interest in biofuels from lignocellulosic feedstock in the United States (US) and the European Union (EU) can provide a path forward toward replacing petroleum-based fuels with sustainable biofuels which have the potential to lower greenhouse gas (GHG) emissions. The selection of biomass conversion technologies along with feedstock development plays a crucial role in the commercialization of next-generation biofuels. There has been synergy and, even with similar basic process routes, diversity in the …

Agenda: A Low-Carbon Energy Blueprint For The American West, University Of Colorado Boulder. Natural Resources Law Center, University Of Colorado Boulder. Renewable And Sustainable Energy Institute, Western Resource Advocates, Rocky Mountain Research Station (Fort Collins, Colo.)

A Low-Carbon Energy Blueprint for the American West (Martz Summer Conference, June 6-8)

The future of the planet may depend upon our ability to increase energy supplies even as we reduce carbon emissions. This conference will address how a low-carbon energy program might evolve with a particular focus on the American West. It will focus on the future of energy in the West--on a “managed transition” to a different energy mix, on the need to nest this effort in a framework that acknowledges interconnections, and on identifying the most salient opportunities to consider the legal, political, financial, and technical challenges.

Unintended Consequences: Potential Downsides Of The Air Force's Conversion To Biofuels, Mark N. Goltz, Charles A. Bleckmann, Charles M. Mackay, Khai Vuong, Jerrod P. Mccomb

Faculty Publications

The desire to reduce US dependence on foreign energy, ongoing environmental concerns, and the rising cost of petroleum have sparked significant development of greener alternative and renewable energy sources such as alcohol-based biofuels. To address these issues, the Department of Defense DOD has moved to diminish its reliance on petroleum for fueling aircraft and ground equipment. The US Air Force, in alignment with DOD objectives, has initiated several goals for reducing its use of energy: (1) decrease the use of petroleum-based fuel by 2 percent annually for the vehicle fleet, (2) increase the use of alternative fuel in motor vehicles …

Developing Criteria For Evaluating The Sustainability Of Emerging Energy, Kurt A. Rosentrater, Elif Kongar

Kurt A. Rosentrater

Over the last decade, the interest in and production of biofuels has grown rapidly. Renewable transportation fuels can be produced from a variety of substrates, using various processing strategies. Feedstock preference and factory scale are geographic dependent. However, it is important to understand the implications of deploying these types of systems on a large scale, both throughout the U.S. as well as globally. To assess the sustainability of various biofuel options, it is crucial to evaluate their performance according to a number of attributes. This has been done using Life Cycle Assessment (LCA). Even so, comparisons among biofuel options are …

Slides: Environmentally Friendly Drilling Systems Program (Efd), Rich Haut

Best Practices for Community and Environmental Protection (October 14)

Presenter: Rich Haut, Houston Advanced Research Center

23 slides

Costs Of Pelleting To Enhance The Logistics Of Distillers Grains Shipping, Kurt A. Rosentrater, Elif Kongar

Kurt A. Rosentrater

Biofuels, especially corn-based ethanol, can help meet some of the increasing demand for transportation fuels. Currently, the most heavily utilized substrate is corn grain, which is readily converted into ethanol at a relatively low cost compared to other biomass sources. The production of ethanol in the U.S. has been dramatically increasing during the last several years; so too has the quantity of manufacturing coproducts. These nonfermentable residues are most often dried and sold as distillers dried grains with solubles – DDGS. Even though these materials are used to feed livestock in local markets, as the size of the industry continues …

Modeling The Effects Of Value-Added Processing And Logistics Using Arena, Kurt A. Rosentrater, Elif Kongar

Kurt A. Rosentrater

Scarcity and cost of nonrenewable fossil fuels have been a growing focus of many energy-dependent nations, including the U.S., for the past couple of decades. There are mainly two ways to approach these problems: (1) reducing the energy dependency and/or (2) developing alternative means of energy production. Utilizing biofuels, which are renewable sources of energy, is a promising way to produce energy. But, as this industry grows, so too does the quantity of byproducts, which are known as DDGS. This paper discusses a model that has been developed to analyze the economic viability of DDGS processing, and includes both deterministic …

Biomass And Biofuels In Maine: Estimating Supplies For Expanding The Forest Products Industry, Jonathan Rubin, Kate Dickerson, Jacob Kavkewitz

Energy & the Environment

This paper estimates the renewable energy potential of Maine’s forest resources, and how much energy these resources could potentially provide the state. Using the most recent state-specific data available, and a methodology similar to the Billion Tons Report, we find that ethanol production from Maine’s forest residues could potentially provide 18% of Maine’s transportation (gasoline) fuels with a fermentation wood to ethanol process. Making Fischer-Tropsch diesel (F-T diesel) using forest residues can replace 39% of Maine’s petro-diesel consumption. Actual levels of biofuels that can be produced will depend on conversion factors and forestry residue removals that are subject to uncertainty.

The Importance Of Emerging Biobased Industries To Engineering And Technology, Kurt A. Rosentrater, R. Balamuralikrishma

Kurt A. Rosentrater

Our society has developed an insatiable demand for energy and material goods. Historically, these needs have been met primarily by fossil fuels and other non-renewable raw materials. As environmental concerns grow, however, renewable resources are gaining increased attention. This paper examines the emergence and importance that biobased industries are increasingly beginning to play. A biobased enterprise, similar in concept to a traditional refinery or factory, utilizes conversion technologies to produce various products. These operations are rapidly increasing both in number as well as in capacity throughout this country, and are poised to add significantly to the nation’s energy and material …

The Global Relevance Of Bio-Based Industries To Engineering And Technology Education, Kurt A. Rosentrater, Radha Balamuralikrishma

Kurt A. Rosentrater

The society in which we live has developed an insatiable demand for energy and material goods. In particular, recent data reveals that the aggressive pursuit of improved standards of living in the highly populated countries of India and China has contributed to increased demand for fossil fuels, which has exacerbated the recent spike in energy costs. Historically, these needs have been met primarily by fossil fuels and other non-renewable raw materials. As environmental concerns grow, however, renewable resources are gaining increased attention. This paper examines the emergence and importance that bio-based industries are increasingly beginning to play. A bio-based enterprise, …

Expanding The Role Of Systems Modeling: Considering Byproduct Generation From Biofuel Production, Kurt A. Rosentrater

Kurt A. Rosentrater

The bioethanol industry has been experiencing rapid growth over the past several years, and is expected to continue to increase production for the foreseeable future. A vital component to the success of this industry is the sales and marketing of processing residues, which are primarily sold as dried distillers grains with solubles (DDGS). Systems modeling, a technique that has been used to predict future demand for bioethanol, can also be used to determine potential byproduct generation rates. This paper discusses the development of one such model, and presents predicted generation of DDGS as well as carbon dioxide emissions from this …