Bioresource and Agricultural Engineering Commons^™

Science And Food Fictions: Agricultural Technologies, The Evolution Of The Modern Industrial Diet, And Calls For A Food Revolution, Tracey Daniels-Lerberg

Green Humanities: A Journal of Ecological Thought in Literature, Philosophy & the Arts

[First paragraph] Individual food choices are culturally and historically contingent practices that arise through an amalgamation of often hidden political, scientific, and economic policies that shape desire and influence access. Food, like all other man-made mechanisms of control and authority, has been used “as a political tool for […] subjugating (either economically or politically) other nations” according to William A. Dando, a professor at the University of North Dakota, who in 1975 urged American agricultural officials not to use food as “a weapon” against starving nations, something he feared was eminently possible given the economic and political climate of agricultural …

Lipid Extraction From Spirulina Sp. And Schizochytrium Sp. Using Supercritical Co2 With Methanol, Shihong Liu, Husam A. Abu Hajar, Guy Riefler, Ben J. Stuart

Civil & Environmental Engineering Faculty Publications

Microalgae are one of the most promising feedstocks for biodiesel production due to their high lipid content and easy farming. However, the extraction of lipids from microalgae is energy intensive and costly and involves the use of toxic organic solvents. Compared with organic solvent extraction, supercritical CO₂ (SCCO₂) has demonstrated advantages through lower toxicity and no solvent-liquid separation. Due to the nonpolar nature of SCCO_2, polar organic solvents such as methanol may need to be added as a modifier in order to increase the extraction ability of SCCO₂. In this paper, pilot scale lipid …

Investigation Of Electrolytic Flocculation For Microalga Scenedesmus Sp Using Aluminum And Graphite Electrodes, Shihong Liu, Husam A. Abu Hajar, Guy Riefler, Ben J. Stuart

Civil & Environmental Engineering Faculty Publications

Electrolytic flocculation using non-sacrificial electrodes with flocculants added was studied on harvesting Scenedesmus sp. In order to optimize the operating conditions of the electrolytic flocculation process and to quantify the amount of flocculants added, aluminum electrodes were first used in the process. It was found that under optimal conditions, the microalgae removal efficiency using aluminum electrodes could reach 98.5%, while 34.2 mg L^-1 of aluminum ions were released during the process. Different metal electrodes were also studied, but high microalgae removal efficiency was witnessed only using aluminum electrodes, indicating the influence of the aluminum ion in flocculation. When non-sacrificial …

Electrochemical Hydrogenation Of Acetone To Produce Isopropanol Using A Polymer Electrolyte Membrane Reactor, Chen Li, Ashanti M. Sallee, Xiaoyu Zhang, Sandeep Kumar

Civil & Environmental Engineering Faculty Publications

Electrochemical hydrogenation (ECH) of acetone is a relatively new method to produce isopropanol. It provides an alternative way of upgrading bio-fuels with less energy consumption and chemical waste as compared to conventional methods. In this paper, Polymer Electrolyte Membrane Fuel Cell (PEMFC) hardware was used as an electrochemical reactor to hydrogenate acetone to produce isopropanol and diisopropyl ether as a byproduct. High current efficiency (59.7%) and selectivity (>90%) were achieved, while ECH was carried out in mild conditions (65 degrees C and atmospheric pressure). Various operating parameters were evaluated to determine their effects on the yield of acetone and …

A Multi-Criteria And Dynamic Sustainability Assessment Of Crop Rotation Alternatives, Saturnina Fabian Nisperos

Computational Modeling & Simulation Engineering Theses & Dissertations

With the food security challenge faced by nations globally, agriculture sustainability has been a significant consideration for concerned agencies. Sustainability assessments are significant tools in providing support to stakeholders in their crop production planning. Agricultural sustainability assessment, however, is complex and it involves numerous criteria that can be conflicting. Limitations on crop rotation sustainability assessment methods include: non-dynamic assessment; lack of regard to cover crops and to the individual crop production preferences of farmers; and focused only on single-year and single-crop rotation. We sought to address these limitations by developing a multi-criteria and dynamic sustainability assessment model that considers the …

Holistic Approach In Microalgae Conversion To Bioproducts And Biofuels Through Flash Hydrolysis, Ali Teymouri

Civil & Environmental Engineering Theses & Dissertations

In recent years, the demand for renewable energy, mainly biomass has increased. The U.S. Energy Information Administration reported that more than 13.3% of the total energy production in the first seven months of 2017 was produced from a biomass source. Among all biomass resources, microalgae has brought a lot of attention due to their numerous advantages such as higher growth rate and productivity compared with the conventional energy crops, higher energy conversion efficiency by photosynthesis, and less water requirement than terrestrial crops. However, its development is far behind industrial production. Several research efforts across the globe have been concerned with …

Testing Effectiveness Of Aqueous Phases From Struvite And Hydroxyapatite Mineral Precipitation As Algal Nutrient Sources, Aaron Lyons

Virginias Collegiate Honors Council Conference

As interest in algal biofuel grows, the need to explore diverse nutrient sources for growing algae becomes apparent. Struvite and Hydroxyapatite (HAP) were precipitated after flash hydrolysis. The leftover aqueous phase (AP) could serve as nutrients source for algae cultivation and the potential reuse of this waste stream is promising. To test this, 12 bottles of Scenedemus sp., four of Struvite, four of HAP, and four control AM-14 synthetic media were cultivated. 10% of the Phosphorus in the synthetic media was replaced with phosphorous from the struvite AP, and 10% of the nitrogen in the synthetic media was replaced …

Investigation Of The Potential For Algaenan To Produce Hydrocarbon Based Fuels From Algae By Hydrous Pyrolysis, Wassim Adel Obeid

Chemistry & Biochemistry Theses & Dissertations

The use of algae as a feedstock for hydrous pyrolysis has a high potential for producing biofuels. The non-food nature of algae in addition to the various advantages associated with the hydrous pyrolysis process makes this combination for the production of biofuels of high interest. However, current results from algae processing have alluded to some challenges: byproducts arising from the thermal transformation of carbohydrates and proteins, which become incorporated in the oil fraction, result in high oxygen and nitrogen contents of the oil. Accordingly, this produces an oil of low quality for refineries. This dissertation investigates use of a pretreatment …

Flash Hydrolysis Of Microalgae Biomass For Biofuels Intermediates Production, Protein Extraction, And Nutrients Recycle, Jose Luis Garcia Moscoso

Civil & Environmental Engineering Theses & Dissertations

Microalgae have shown much higher growth rates and productivity when compared to conventional agricultural crops, aquatic plants and tree species, requiring much less land area than other biodiesel feedstock. To harness that potential the hydrothermal liquefaction of algae biomass was studied and a new process called "Flash Hydrolysis" was developed to use water under subcritical conditions, this process capitalizes on the difference in reaction kinetics of algae polymeric components and fractionates proteins in liquid phase in seconds of residence time.

The main objectives for this study are: Analyze the effect of temperature in FH process to maximize the extraction of …

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 …

Genetic Algorithm-Based Model For Determination Of Efficient Management Strategies For Irrigation Canal Networks, Talaat Taher El Gamel

Civil & Environmental Engineering Theses & Dissertations

An optimization model for the determination of efficient management strategies for an irrigation canal network is developed. The objective is to minimize the total water consumed while satisfying various system constraints. An unsteady flow model is used to simulate the flow in the network. A genetic algorithm- (GA-) based framework is used to solve the model. The suitable GA parameters that should be used within the model, as well as the performance of various constraint-handling techniques, are studied. Uncertainties in crop pattern and water consumption rates are incorporated into the search procedure to identify more reliable solutions. A graphical interface …