Civil and Environmental Engineering Commons^™

Investigating The Effectiveness Of Microplastic Removal And The Relationship Between Microplastics, Bacterial Communities, And Nitrogen Cycling In The Natural Treatment Systems At The Arcata Wastewater Treatment Facility, Fiona Connor

Cal Poly Humboldt theses and projects

This thesis addressed two challenging aspects of microplastic research, including the quantification of microplastics in organic-rich water, and the investigation of how microplastics impact microorganisms and related nutrient-cycling. Two projects were designed and executed to address specific research objectives relating to these broad topics. The first objective was to develop and implement methods to determine the effectiveness of microplastic removal across the natural treatment systems at the Arcata Wastewater Treatment Facility (AWTF). The second objective was to observe how microplastics found in domestic wastewater impact the bacterial communities and nitrogen cycling in freshwater treatment wetland sediment through a bench-scale experiment, …

Effect Of Bioaugmentation Product Biowish® Aqua™ On Nitrogen Removal In Wastewater, Patrick Cassidy Kalvass

Master's Theses

Biological nutrient removal (BNR) from wastewater, and specifically nitrogen removal, is a growing concern to wastewater dischargers such as municipalities. Excess nutrients in effluent can create problems such as eutrophication, toxicity to aquatic life, and dissolved oxygen depletion in receiving waters. BNR systems have been installed in many locations with success, but their operation presents operational and financial demands greater than conventional biological treatment. Nitrogen removal is typically performed in sequential autotrophic nitrification and denitrification, which increases needed energy input, operational complexity, and therefore cost. Simultaneous nitrification-denitrification (SNdN) achieved in a single system has also been successfully implemented, however operational …

Microbial Dynamics And Design Considerations For Decentralized Microbial Fuel Cell Applications, Cynthia Castro

Doctoral Dissertations

The purpose of this dissertation was to assess the practicality of using microbial fuel cells (MFCs) as alternative sanitation systems for wastewater treatment and energy recovery, focusing on identifying key design considerations for treating high strength wastewater and managing alternative metabolic pathways. We evaluated the energetic outputs of a lab-based pilot MFC designed to treat complex organics present in both synthetic feces and municipal wastewater. The pilot MFC produced two energetic products, methane and electricity, when treating two types of complex wastewaters. The energetic products associated with anode respiration and methanogenesis were simultaneously observed and yielded a combined energy ouput …

Production And Harvest Of Microalgae In Wastewater Raceways With Resource Recycling, Alexander Colin Roberts

Master's Theses

Microalgae can be grown on municipal wastewater media to both treat the wastewater and produce feedstock for algae biofuel production. However the reliability of treatment must be demonstrated, as well as high areal algae productivity on recycled wastewater media and efficient sedimentation harvesting. This processes was studied at pilot scale in the present research.

A pilot facility was operated with nine CO₂-supplemented raceway ponds, each with a 33-m² surface area and a 0.3-m depth, continuously from March 6, 2013 through September 24, 2014. The ponds were operated as three sets of triplicates with two sets continuously fed …

Development And Application Of An F/M Based Anaerobic Digestion Model And The Rt-Ribosyn Molecular Biology Method, Matthew Raymond Cutter

USF Tampa Graduate Theses and Dissertations

A simple anaerobic digestion model has been developed for a continuously-stirred tank reactor (CSTR), which links the specific biogas production rate to the food/microorganism ratio (F/M). The model treats the various microbial populations involved in the sequential biological processes involved in anaerobic digestion as a composite and links the entire biomass specific growth rate directly to the specific biogas production rate. The model was calibrated by determining the specific gas production rate for a range of F/M values using a municipal wastewater seed sludge. The model predictions for steady-state biogas production rates were compared to observed biogas production and volatile …