Engineering Commons^™

Methane Emission Treatment And Potential Upcycling Using Methylomicrobium Alcaliphilum, Jace Parkinson

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Anthropogenic methane emissions are harmful to the environment and can be difficult to treat. Use of M. alcaliphilum for bioremediation of methane looks to be one of the most promising methods of reducing the negative environmental impacts of methane emissions while simultaneously providing an economic incentive. Successful bioreactor design for M. alcaliphilum based methane treatment requires biokinetic constants and microbial growth information. Methods were established for determining biokinetic constants, including growth rate, biomass yield, specific methane consumption rate, and a correlation between methane oxidation and carbon dioxide production for M. alcaliphilum. Values determined for these constants were used to …

Integrated Life Cycle And Techno-Economic Assessment Of The Conversion Of High Productivity, Low Lipid Algae To Renewable Fuels, Chad R. De Mill

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The production of alternative transportation fuels is imperative to meet future energy demands without contributing to global climate change. Advances in alternative processing techniques that have emerged due to interest in microalgae as a feedstock have led to a variety of potential processing pathways for the production of bio-based fuels. A major hurdle in the algal production process is maintaining a fast and stable algae culture. Monocultures, developed for their high lipid content, suffer from low productivity, are susceptible to crashes and require a constant supply of carbon dioxide to maintain productivity. In an effort to circumvent these obstacles, algal …

Lifecycle Assessment Of Microalgae To Biofuel: Thermochemical Processing Through Hydrothermal Liquefaction Or Pyrolysis, Edward P. Bennion

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Microalgae have many desirable attributes as a renewable energy recourse. These include use of poor quality land, high yields, and it is not a food recourse. This research focusses on the energetic and environmental impact of processing microalgae into a renewable diesel. Two thermochemical bio-oil recovery processes are analyzed, pyrolysis and hydrothermal liquefaction (HTL). System boundaries include microalgae growth, dewatering, thermochemical bio-oil recovery, bio-oil stabilization, conversion to renewable diesel, and transportation to the pump. Two system models were developed, a small-scale experimental and an industrial-scale. The small-scale system model is based on experimental data and literature. The industrial-scale system model …

Systematic Framework For Evaluating Treated Wastewater Usage In Agricultural Irrigation, Yasser Kamal Nazzal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A general systematic framework with several sub-frameworks was developed to help managers make informed decisions related to the reuse of treated wastewater in agricultural irrigation. The framework involves the identification and evaluation of the short- and long-term effects of using treated wastewater with some common constituents of concern (e.g. salts and some specific ions, nutrients, heavy metals, organic compounds, and microorganisms) on the environmental elements (crop, soils, surface water, and groundwater), and on the public health. Local and/ or international standards, criteria, and guidelines related to agricultural reuse are applied to the evaluation of the effects. Based on the evaluation …

Estimation Of Crop Evapotranspiration By Means Of The Penman-Monteith Equation, Paul J. Vanderkimpen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study evaluated the potential of using simple, semi-empirical resistance models for the direct estimation of crop evapotranspiration as an alternative to the traditional approach involving a reference equation and a crop coefficient. It consisted of three major parts.

The first part originally aimed at the development of simple expressions for the aerodynamic and surface resistance terms in the Penman-Monteith equation. This goal could not be achieved because of two reasons: First, the determination of aerodynamic resistance was rendered impossible because of problems with the measurements, and, secondly, the values of surface resistance, back-calculated from the Penman-Monteith equation, turned out …

Highway Drain Depth And Soil Stability, Mizher Al-Himdani

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The presence of moisture in the soil reduces its shear strength. After the rain or snowmelt, the high percentage of moisture in the subgrade of highway, causes the instability resulting into failure of the highway due to high water table. Therefore, it is essential to install a drainage system to remove the excess moisture from the subgrade of highways to avoid its failure.

In the present study, six different soil samples have been studied to observe its failure by triaxial shear strength and corresponding moisture content was noted. The tension applied to remove moisture was converted to equivalent drain depth. …

The Vertical Distribution Of Salts In A Soil Profile During The Drainage Process, Adel Taha Yassin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to develop a model to predict water extraction patterns and therefore salt distribution patterns in a one dimensional homogeneous soil profile for a specified root distribution.

Water extraction was simulated as a function of the total potential and the root density at any level of the profile.

Salt redistribution caused by irrigation was simulated by assuming a partial and proportional displacement of the water in each soil layer.

A computer program was written for the model in Fortran language and implemented on the Vax. To evaluate the performance of the model, test studies were …