CBEE wins first and second place in research competition

Two students working with Dr. Lee Blaney, professor in chemical, biochemical and environmental engineering, participated in the student poster competition at the 2024 Chesapeake American Water Work Association and Chesapeake Water Environment Association (CSAWWA/CWEA) Joint Spring Meeting in Perryville, MD in May. 

The students received the top two awards in the poster presentation competition. 

First Place -- Sahar Souizi, environmental engineering doctoral student

Second Place -- Margaret Siao,’23 chemical engineering biotechnology and bioengineering track, chemical and biochemical engineering master’s student and an ICARE fellow. 

Sahar Souizi 

Poster Title: Sustainable and rapid nutrient recovery by advanced Donnan dialysis reactors.

Authors: Sahar Souizi, An Hong Dang, Hui Chen, Lee Blaney

Abstract: Donnan dialysis leverages electrochemical potential gradients across ion-exchange membranes to selectively separate nutrients from wastewater. This project aimed to improve the rate of nutrient recovery and scale-up potential through development of novel Donnan dialysis reactors.

A batch-recycle system was used to evaluate the impacts of mixing, flow rate, and waste-to-draw solution volume ratio. With the optimal conditions, 90% orthophosphate recovery was achieved, and nutrient flux was increased by 30%. These results informed development of modular, tube- in-tube Donnan dialysis reactors, which enabled rapid nutrient recovery as struvite. These results support the role of Donnan dialysis systems to achieve circular nutrient economies.

Margaret Siao

Poster title: Influence of water quality on PFAS uptake by ion-exchange membrane-based passive samplers.

Authors: Margaret Siao, Donya Hamidi, Alvin Bett, Ke He, Lee Blaney

Abstract: Recently, per- and polyfluoroalkyl substances (PFAS) were regulated in drinking water. Many monitoring studies have reported variable PFAS concentrations in water resources. To inform the long-term, average PFAS levels, we developed and validated the performance of a novel passive sampling device comprised of anion-exchange membranes. Impacts of solution pH, salinity, and dissolved organic matter were evaluated for over 20 PFAS. Equilibrium PFAS and chloride concentrations were measured in the water and membrane phases and used to calculate selectivity coefficients. Trends between selectivity coefficients and PFAS properties enabled generation of a universal calibration for passive sampler deployment in different water sources.