Environmental Engineering Commons^™

Methane Production By A Packed-Bed Anaerobic Digester Fed Dairy Barn Flush Water, Sean Richard Thomson

Master's Theses

Packed-bed digesters are an alternative to covered lagoon digesters for methane production and anaerobic treatment of dilute wastewaters such as dairy barn flush water. The physical media of packed-beds retain biofilms, often allowing increased treatment rates. Previous studies have evaluated several types of media for digestion of dilute wastewaters, but cost and media fouling have setback commercial development. A major operational cost has been effluent recirculation pumping.

In the present effort, a novel approach to anaerobic digestion of flush dairy water was developed at pilot-scale: broken walnut shells were used as a low-cost packed-bed medium and effluent recirculation was replaced …

Photobioreactor Design For Improved Energy Efficiency Of Microalgae Production, Alexander Burns

Master's Theses

ABSTRACT

Photobioreactor Design for Improved Energy Efficiency of Microalgae Production

Alexander Burns

The objective of this research was to investigate a new photobioreactor (PBR) design for microalgae production that retains the typical advantages of existing tubular PBRs while reducing power consumption by providing simultaneous culture circulation and gas exchange with airlift alone and no centrifugal recirculating pump. Traditional tubular PBR designs feature a compressed air supply and a centrifugal pump for culture circulation and gas exchange. Circulation and gas exchange in a closed-system PBR is necessary to keep the algae suspended and to provide sufficient mass transfer (mainly for the …

Field And Greenhouse Studies Of Phytoremediation With California Native Plants For Soil Contaminated With Petroleum Hydrocarbons, Pahs, Pcbs, Chlorinated Dioxins/Furans, And Heavy Metals, Matthew Robert Poltorak

Master's Theses

Native and naturalized California plant species were screened for their phytoremediation potential for the cleanup of soil contaminated with petroleum hydrocarbons (PHCs), poly-aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), chlorinated dioxins/furans, and heavy metals. This screening was followed by controlled greenhouse experiments to further evaluate the phytoremediation potential of the best candidates. Field specimens and soils used for this study were collected from the former Energy Technology Engineering Center (ETEC) at the Santa Susana Field Laboratory in Southern California that was operated by the Department of Energy (DOE). Soils at this site contain all of the contaminants of interest (COIs). Nine …

Growth Media And Lipid Determination Comparison Of High Rate Algae Ponds, Eric Alexander Nicolai

Master's Theses

Growth Media and Lipid Determination Comparison

of High Rate Algae Ponds

Eric Alexander Nicolai

The feasibility of algal biofuel production relies on the use of a non-potable water source. Municipal wastewater is nutrient-rich and a cost effective option as a growth media in algae ponds. However, this resource may be too valuable for algal biomass production, as reclaimed wastewater is needed for surface irrigation and groundwater recharge. This thesis compares the performance of 4.2 m² high rate algal raceway ponds (HRAPs) to 33 m² HRAPs grown on primary settled wastewater during a media recycling study and a growth …

Treatment Of Nitrogen Oxides By Chlorella Vulgaris Algae In Photobioreactors, Steven Shihady

Master's Theses

The effectiveness of algae to treat NO₂and NO in simulated flue gas was tested using Chlorella vulgaris in photobioreactors (PBRs) using NO_xconcentrations between 30 ppm to 780 ppm. NO_xdissolved and reacted in water to form NO₃^-and NO₂^-in the PBR growth medium, providing a nitrogen source that the algae readily assimilated for cell synthesis. Three 20-L photobioreactors were inoculated with a pure culture of C. vulgaris prepared in Bristol growth medium and algae were grown in the PBRs at 25°C and pH of 7.0 in a modified Bristol medium …

Avoided Water Cost Of Electricity Generation For Solar Pv And Wind Technologies In Southern California, Matthew Cohen

Master's Theses

The objective of this thesis is to provide a foundation for evaluating the water costs associated with electricity production to calculate the avoided water cost of energy for solar PV and wind technologies relative to coal, natural gas, nuclear, geothermal, concentrated solar thermal, and biomass. Water consumption is estimated for energy production (fuel extraction and preparation) and electricity generation (power plant operation) using the best available information from published articles. The quantity of water consumed for electricity production is monetized for a Southern California case study based on the water rates of Metropolitan Water District of Southern California (MET), which …

The Effect Of Pretreatment Methods On Methane Yield And Nutrient Solubilization During Anaerobic Digestion Of Microalgae, Alexander Scott Hill

Master's Theses

Microalgal biomass is a candidate feedstock for biofuel production. To improve the sustainability of algae biofuel production, following biofuel recovery, the biomass nutrients should be recycled for additional algae growth. Anaerobic digestion of algae or oil-extracted algae is a means of recovering carbon and other nutrients, while offsetting algae production electricity demand. The major limiting factor in microalgae digestion is the low biodegradability of the cell walls. In the present study, various pretreatment technologies were tested at bench scale for their ability to improve raw, non-lipid-extracted algae biodegradability, which was assessed in terms of methane yield, volatile solids destruction, and …

Water And Nutrient Recycling In High Rate Algae Ponds Fed In Primary Treated Municipal Wastewater, Michael Field Chang

Master's Theses

Algal biofuels present a promising future alternative to petroleum based fuels. Water nutrient recycling is a key step to increase the sustainability of algae biofuel production facilities. This thesis discusses the process of nutrient and water recycling in high rate algae raceway ponds (HRAP) fed primary treated municipal wastewater. Research was conducted primarily at the San Luis Obispo Water Resource Reclamation Facility (SLOWRRF). Nine 30 m², 0.3 m deep HRAP’s were operated continuously from June 1, 2013 to April 17, 2014. The ponds were arranged in three sets of triplicate ponds, with two pond sets run on 3-day …

Thermal Numerical Analysis Of Vertical Heat Extraction Systems In Landfills, Michael Thomas Onnen

Master's Theses

An investigation was conducted to determine the response of landfills to the operation of a vertical ground source heat pump (i.e., heat extraction system, HES). Elevated landfill temperatures, reported various researchers, impact the engineering performance of landfill systems. A numerical model was developed to analyze the influence of vertical HES operation on landfills as a function of climate and operational conditions.

A 1-D model of the vertical profile of a landfill was developed to approximate fluid temperatures in the HES. A 2-D model was then analyzed over a 40 year time period using the approximate fluid temperatures to determine the …