Decreasing Solid Retention Time of Aerobic Granular Sludge for Improved Wastewater Treatment

PROJECT NUMBER: 34

AUTHOR: Sadie Jonson, Geology and Geological Engineering | AUTHOR: Faylyn Bruecken, Civil and Environmental Engineering

MENTOR: Rudy Maltos, Civil and Environmental Engineering | MENTOR: Tzahi Cath, Civil and Environmental Engineering

ABSTRACT

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Wastewater treatment has been crucial to the development of cities around the world. However, many current wastewater treatment plants (WWTP) were built in the 1970s and 80s and require upgrades or costly expansions to accommodate increasing wastewater flows. One method that can be employed at WWTPs 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 without expanding their treatment footprint. This study investigates the removal of poor settling floc that prevents the formation of AGS. One problem that prevents WWTPs from adopting AGS is the required solid retention time (SRT), the amount of time that the solid fraction of the microbial floc spends in a treatment unit. Typical AGS systems use long SRTs above 30 days while traditional WWTPs have SRTs between 8-15 days. To decrease SRT, a hydraulic selector (HS) has been developed to remove poor settling floc allowing AGS to develop and increase remaining floc settling time. Results have shown that the HS has helped to decrease the SRT of the bioreactor and promoted the generation of AGS within 60 days.

VISUAL PRESENTATION

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AUTHOR BIOGRAPHIES

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Sadie is a freshman at Colorado School of Mines. She is pursuing a BS in Geological Engineering. She became a member of the FIRST Fellowship in August of 2019 and had been working with Rudy Maltos and other undergraduates at the Mines Park Wastewater Treatment plant since the fall of 2019.

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Faylyn Bruecken is a sophomore at Colorado School of Mines. She is pursuing a BS in Environmental Engineering in the CEE department. She became a ReNUWit Research Scholar last November and works with Rudy Maltos and other undergraduates to perform testing and analyze data from the Mines Park wastewater treatment plant.

Sponsored by Phillips 66