Meet the Researcher - Sadie Jonson

Breakout Room: 10

SadieJohnsonResearcher Name: Sadie Jonson
Title of Research: Decreasing Solid Retention Time of Aerobic Granular Sludge for Improved Wastewater Treatment
Division Representing: Engineering
Institution: Colorado School of Mines
Institution Location: Colorado
Home State: Colorado
District Number: 7
Advisor/Mentor: Tzahi Cath
Funding Source: FIRST Fellowship Funding; National Science Foundation and ReNUWIt

Research Experience:  
Growing up hiking and backpacking through the mountains of Colorado, pursuing a degree in Geologic Engineering has always been the path for me to pursue my passions of both geology and helping the community. I choose to attend Mines for the research and other extra-curricular activities that help foster and build leadership skills. I was fortunate to be invited to be a part of the Vanguard Scholars Program, a community of scholars for high-potential women students possessing leadership skills and the desire to improve our world through science, technology, engineering and mathematics. During my freshman year at Mines, I was awarded the Freshman Innovation and Research Scholar Training (FIRST) fellowship to conduct research. I got the opportunity to work with Prof. Cath's research group, where I was tasked with optimizing the wastewater treatment process and to date, I continue to conduct research and maintain wastewater bioreactors in the lab. When I am not in the lab, I enjoy working as a graphic artist for Mines' newspaper, The Oredigger. I was recently appointed as the secretary of Mines Society of Women in Geoscience chapter, a position that I hope to bring new ideas to foster a strong sense of community. In the future I aspire to use my degree and knowledge to work on issues of groundwater hydrology and water quality.

Presentation Experience: 
My leadership role in high school and my volunteer work provided me an opportunity to present to a diverse audience. While at Mines, I continue to engage and educate my peers and the community in various capacities. At the Geoscience Society of Women's meetings, I routinely present on event planning and keep members up to date on relevant information. I had an exciting opportunity to do a product pitch to the Mines community as a part of the Design course. While working to address issues of outdated infrastructure, my design group presented our proposed solution of modified airline seats that could maximize customer satisfaction without the need to completely redesign the interior arrangement of commercial airplanes. While the set-up of this solution was completely hypothetical, it gave me experience with how to present information to an audience of potential investors, and how to ‘sell' the value of a product. In the realm of research, I was able to present my research at my university's Undergraduate Research Symposium last spring. While this presentation was completely virtual, due to COVID-19 restrictions, this presentation allowed me to gain experience presenting research in a way that is approachable and cohesive for all audiences. All of this past presentation experience makes me confident that I can deliver an engaging and informative presentation to congressional staff at this event.

Significance of Research:       
Wastewater treatment has been crucial to the development of cities and reducing pollution of the environment. However, many current wastewater treatment plants (WWTP) were built dozens of years ago and require upgrades or costly expansions to accommodate increasing flows and removal of emerging contaminants. One method that can be employed at WWTPs to increase capacity is an aerobic granular sludge (AGS) treatment process. AGS is a dense microbial community that consumes carbon, nitrogen, and phosphorus and settles quickly, allowing WWTPs to treat more wastewater at similar footprint. One problem that currently prevents WWTPs from adopting AGS is the required high solid retention time (SRT), the average time that the biosolids spend in the treatment unit. Typical AGS systems require close to 6 months to develop. Dense AGS settles quickly and efficiently removes organics and nutrients from the wastewater. The study that I am conducting investigates the removal of poor settling floc that prevents the formation of AGS. To reduce AGS formation time while maintaining a low SRT, a novel hydraulic selector (HS) was developed in our research to remove poor settling floc. This hydraulic selector acts as a sludge vacuum system suspended within the bioreactor; it selectively removes poor settling floc, allowing AGS to develop rapidly, and substantially increase the settling velocity of the remaining floc. Results have shown that HS decreased the SRT of the bioreactor and promoted the generation of AGS within only 2 months, resulting in ~65 % potential increase in the capacity of existing WWTPs.   

Uniqueness of Research: 
This research will lead to upgrade of existing wastewater treatment facilities to accommodate increased wastewater flows with a technology that can be inexpensively and rapidly integrated into existing infrastructure. The novel hydraulic selection process can increase the overall treatment efficiency, reduce the treatment time, and enhance the capabilities.