Analytical and Data-driven Models to Predict Algae Biofilm Growth in Wastewater Treatment

Dylan Ellis, Gerald Jones, Ronald Sims, and Jia Zhao Department of Biological Engineering and Department of Mathematics and Statistics, 4100 Old Main Hill Logan, UT 84322

Harmful algal blooms (HABs) are a growing public health concern both nation and worldwide.
Last year there were 25 major sites of HABs in the state of Utah alone. These blooms are caused
in part by excess nutrients (nitrogen and phosphorus) being discharged from wastewater
treatment plants (WWTPs). To combat the growing prevalence of HABs the state of Utah is
imposing new nitrogen and phosphorus effluent standards for WWTPs. Utah State University is
working in collaboration with Central Valley Water Reclamation Facility (CVWRF), the largest
municipal WWTP in the state of Utah treating 60 million gallons per day, and WesTech
Engineering-Inc. to develop a novel biological process to help WWTPs meet these new
standards. This process is the rotating algae biofilm reactor (RABR) that removes nutrients from
wastewater by producing algae biomass that can be used in bioproduct production. The RABR
consists of disks rotating through a growth substrate (wastewater) to produce an attached growth
biofilm and remove nutrients from the substrate. This biofilm can be mechanically harvested and
converted into value-added bioproducts including biofuels, bioplastics, animal feed, and
fertilizers. Extensive research has been conducted on the RABR at laboratory and pilot scales,
but in preparation for scale-up and industrial applications a mathematical model describing the
system must be developed. Due to high concentrations of nitrogen and phosphorus in the growth
substrate and high summertime light intensity, the system is often light inhibited. An analytical
model has been adapted from work performed by Bara and Bonneford that describes light limited
algae growth. This model will be augmented using sparse identification of nonlinear dynamics
(SINDy), a data-driven approach allowing for the identification and development of important
growth terms, on data previously collected from the RABR at laboratory and pilot scales along
with data currently being collected.

Additional Abstract Information

Presenters: Dylan Ellis, Gerald Jones

Institution: Utah State University

Type: Poster

Subject: Biological & Chemical Engineering

Status: Approved

Time and Location

Session: Poster 2
Date/Time: Mon 3:00pm-4:00pm
Session Number: 2555