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Increasing Algal Productivity And Treatment Potential In Raceways Fed Clarified Municipal Wastewater, Christopher D. Pittner

Master's Theses

Two sets of triplicate pilot algal raceway ponds (1000-L, 0.30-m deep, paddle wheel mixed) were operated for 14 months at a California wastewater treatment plant to treat wastewater and generate algal-bacterial biomass as biofuel feedstock. Two experiments were run to determine the effect on biomass productivity of (1) hydraulic residence time (HRT: 2, 3, 4, or 4.5 days) and (2) feeding schedule (18 small pulses during 8 AM-4 PM [diurnal] versus 20 large pulses during 4 AM-12 AM [diel]). The target productivity was at least 20 g volatile suspended solids per m2 of pond per day. Additional output variables were …

Settling Performance In Wastewater Fed High Rate Algae Ponds, Elliott Blake Ripley

Master's Theses

Although high rate algae ponds (HRAPs) are a proven wastewater treatment technology with numerous environmental, social, and economic benefits, their widespread use has been hindered by inconsistent and unreliable settling performance. Hence, the goal of this thesis is to investigate how specific operational parameters affect the settling performance of HRAPs. Nine HRAPs (30 m² surface area, 0.3 m depth) were operated as three triplicate sets, with each set run on either a 2, 3, or 4 day HRT continuously from January 25, 2012 through April 11, 2013. Settling performance was determined (i) by measuring the TSS of Imhoff cone …

Bioflocculation Of Wastewater Treatment Pond Suspended Solids, Louis Lefebvre

Master's Theses

Bioflocculation of Wastewater Treatment Pond Suspended Solids

Louis Lefebvre

Wastewater treatment lagoons and high rate algae ponds (HRAPs) can provide cost effective wastewater treatment, but they commonly have high effluent concentrations of total suspended solids (TSS). In this thesis algae pond effluent was treated in a beaker testing apparatus (mixed and aerated) with various mixtures of activated sludge and primary effluent simulating differing activated sludge aeration basin compositions then was allowed to settle to assess settleability. Conventionally, microalgal suspended solids are removed by chemical coagulation followed by separation methods that often have a high cost relative to the low cost …

Improved Microalgal Biomass Harvesting Using Optimized Environmental Conditions And Bacterial Bioflocculants, Derek C. Manheim

Master's Theses

ABSTRACT

IMPROVED MICROALGAL BIOMASS HARVESTING USING OPTIMIZED ENVIRONMENTAL CONDITIONS AND BACTERIAL BIOFLOCCULANTS

DEREK CONTE MANHEIM

The cost and energy balance of microalgae biofuel production is sensitive to the algae harvesting method, among many other factors. Bioflocculation and settling of suspended microalgae cultures is a harvesting method with potentially low cost and energy input. However, bioflocculation (the spontaneous flocculation of algal cells without chemical addition) has not been a reliable process with cultures grown in ponds. To provide insights to help improve algae settling, factors affecting the settling of algae were investigated in the laboratory using pure cultures of two common …

Bioflocculation For Control Of Wastewater Pond Microalgae, Daniel Thomas Frost

Master's Theses

Investigates several hypotheses regarding the use of bioflocculation as a harvesting method for wastewater pond microalgae. Research performed on pilot-scale high rate ponds (HRPs) on the California Central Coast.