Biological Engineering Commons^™

Population Analysis Of Cyanobacteria In Rotating Algal Biofilm Reactors, Eric H. Matthews

All Graduate Theses and Dissertations, Fall 2023 to Present

Algal biofilms have numerous applications in wastewater treatment and bioproduct production. The Sustainable Waste-to-Bioproducts Engineering Center at Utah State University is working to develop rotating algal biofilm reactors (RABRs) to remove excess nitrogen and phosphorus from wastewater effluent while producing biomass for downstream production.

Genetic analysis of algal biofilms on various RABRs was performed to gain improved understanding of the biofilm populations. This analysis focuses on a pilot-scale RABR and how it compares to several other RABRs. Additionally, old methods of genetic analysis filtered out important cyanobacterial populations. A new method was developed to identify the cyanobacteria within the biofilms. …

Aerobic Biodegradation Of Algae-Derived Bioplastics Under Controlled Composting Conditions, Clayton J. Lords

All Graduate Theses and Dissertations, Fall 2023 to Present

Plastics are versatile polymers that have become critically important materials in many industries. Although plastics are important and useful materials, they account for vast amounts of environmental pollution and climate change contribution. Sustainable bioproducts are becoming increasingly important in the effort to mitigate the impacts of pollution and climate change. The scale of environmental damage caused by plastic pollution highlights the need to implement sustainably sourced biodegradable plastics within the global economy. Bioplastics are materials that may be manufactured from biological materials or can biodegrade under certain conditions. Algae are microorganisms that can be grown using nutrient-rich municipal wastewater; the …

Modeling The Production Of Microalgal Biomass In Large Water Resource Recovery Facilities And Its Processing Into Various Commodity Bioproducts, James Pierson, Gopi Raju Makkena, Sandeep Kumar, Vinod Kumar, Vivekanand Vivekanand, Hasan Husain, Muhammad Ayser, Venkatesh Balan

Civil & Environmental Engineering Faculty Publications

Algae are capable of sequestering nutrients such as nitrates and phosphates from wastewater in the presence of sunlight and carbon dioxide (CO₂) to build up their body mass and help combat climate change. In the current study, we carried out different case studies to estimate the volume of algal biomass that could be produced annually using the rotating algal biofilm (RAB) method in three large-scale water resource recovery facilities (WRRFs) in Texas: Fort Worth, Dallas, and Houston. We calculated the total amount of lipids, carbohydrates, and proteins that could be fractionated from the algal biomass while using the …

Effect Of Hydrogen Peroxide On Algae And Microcystin In Control And Lake Waters, Tatiana Castillo Hernandez

Biological and Agricultural Engineering Undergraduate Honors Theses

Cyanobacteria are photo-autotrophic organisms with a worldwide distribution, which can result in Harmful Algal Blooms (HABs) producing toxins. One of the most common strains of cyanobacteria is Microcystis, which produces the most abundant cyanotoxin, microcystin. In this study, we analyzed the effect of H₂O₂ on algae and microcystin using both lake and reagent grade water. The first objective was to determine the effect of H₂O₂ on algae and cyanobacteria in lake water that was nutrient enriched. The second objective was to detect the effect of H₂O₂ at oxidizing microcystin in …

Adaptive Laboratory Evolution Of Scenedesmus Obliquus For Increased Carbohydrate Content And Biomass Productivity, Nahel Ali

Master's Theses

The economics of microalgal bioproduct commercialization would benefit from increased accumulation of energy storage compounds, such as carbohydrates and lipids, and increased biomass productivity. This thesis explores two adaptive laboratory evolution strategies for improving Scenedesmus obliquus: single UV-mutagenesis and low light cultivation at a high dilution rate to produce cultigens with greater carbohydrate content and iterative UV-mutagenesis and selection under outdoor conditions in a raceway pond at a high dilution rate to increase biomass productivity.

Two cultigens were generated with the goal of increased carbohydrate content: K5 and K7. Both were mutagenized for 5 seconds and cultivated in 50-mL …

Methods To Increase Algae Biomass Productivity In Raceway Pond Monocultures, Ryan S. Anderson

Master's Theses

The economics of algae biofuels and bioproducts would be improved by increased biomass productivity. Two studies on this potential are described in this thesis – one on a locally isolated filamentous yellow-green alga and the other on a planktonic strain genetically improved via selective enrichment.

Polycultures have been viewed as productive, stable, and, in some cases, harvestable by natural bioflocculation. Local native strains might have higher productivity than culture collection strains because they are already adapted to local outdoor conditions. In this study, the filamentous yellow-green alga Tribonema minus was isolated from a local volunteer polyculture. Its productivity as a …

Optimization Of Biogas Production By Use Of A Microbially Enhanced Inoculum, Anna Doloman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A renewable energy source, biogas, comprises of methane (80%) and carbon dioxide (15%), and is a great alternative to the conventional fossil-based fuels, such as coal, gas and oil. Biogas is created during anaerobic biological digestion of waste materials, such as landfill material, animal manure, wastewater, algal biomass, industrial organic waste etc. A biogas potential from organic waste in the United States is estimated at about 9 million tons per year and technology allows capture of greenhouse gases, such as methane and carbon dioxide, into a form of a fuel. In the light of global climate change and efforts to …

Nutrient Limitation Of Algal Growth In Fishery Lakes, Madeline Ludwig

Biological and Agricultural Engineering Undergraduate Honors Theses

This study investigated the effect of nutrient addition on algal growth in three United States Forest Service lakes for fishery management in Arkansas. In fishery managed lakes, fertilization works by manipulating algae growth, a basal food resource in lakes, to promote the growth of the fish population. For the nutrient addition experiments, water was collected from each lake in cubitainers and spiked with nutrients; the treatments included the control, nitrogen (+N), phosphorus (+P), and nitrogen and phosphorus (+N +P). When algal growth was visually observed, a water sample was collected from each cubitainer and analyzed for chlorophyll-α. The results showed …

Anaerobic Co-Digestion Of Algal Biomass And A Supplemental Carbon Source Material To Produce Methane, Yousef Soboh

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The demand on alternative energy is rapidly increasing because the reserves of conventional fuel are decreasing and their impacts on the environment are increasing.
Developing renewable energy sources should receive utmost attention. The production of biofuels like methanol, biodiesel, and methane from various kinds of abundant biomass represents a very attractive energy source that can reduce the dependence on conventional fossil fuels energy.

Since algae contains high amounts of nitrogen and low carbon content, this research focused on anaerobic fermentation of algae to produce methane by blending algae with a supplemental carbon source material, sodium acetate. This was done to …

Pretreatment Of Scenedesmus Sp. Biomass As A Potential Anaerobic Digestion Substrate, Xinyi E, Czarena Crofcheck

Biosystems and Agricultural Engineering Faculty Publications

Algal biomass can be a potential substrate for anaerobic digestion. However, raw algae cells show a resistance to biological degradation, resulting in a slower methane production rate. Varying thermal and chemical pretreatments of algal biomass were investigated in an attempt to increase soluble organic matter (SOM) yield, which would result in enhanced methane production during subsequent anaerobic digestion. Scenedesmus sp. was harvested using three different procedures: with flocculation, with flocculation and drying, and without flocculation or drying. For all pretreatments and algae types, fluorescence micrographs were obtained to visually confirm the degradation of the algal cell walls. A complete 2 …