Turning Wastewater into a Resource: A Graduate Student’s Solution to Climate Change

(UCLA Samueli) These days, civil and environmental engineering doctoral student Kevin Clack spends his time investigating innovative ways to improve water resilience in arid metropolitan regions such as Los Angeles, but he didn’t always know he wanted to pursue a career in engineering.

Growing up in Orange County, California, Clack was a cross-country and track runner in high school with no particular interest in environmental-related topics. He attributes his initial intrigue to his high school biology and physics teachers who made science interesting by emphasizing its impact on our daily lives.

“My teachers made environmental topics relatable, exciting and sometimes even scary,” Clack said.

Without a true sense of direction after high school, he planned to attend community college to continue running and to complete his general education before transferring to a four-year university. Instead, Clack says, “[he] was lucky to be accepted into San Diego State University (SDSU) after being waitlisted.”

Clack decided to study environmental engineering at SDSU, where he met an inspiring professor, Natalie Mladenov, who runs the Water Innovation & Reuse Lab. Mladenov was encouraging students to apply for a National Science Foundation International Research Experience for Students on Sustainable Sanitation (NSF-IRES) program, which gave students the opportunity to study decentralized wastewater treatment systems (DEWATS) and sustainable sanitation solutions in peri-urban areas of Durban, South Africa.

Clack applied and was accepted to the program and soon found himself learning about sustainable sanitation and resource recovery solutions from local professors, engineers and students.

“It was such an eye-opening experience to learn about how other people lived and how other people addressed solutions related to clean water and sanitation,” Clack said.

In collaboration with local students and professors, this experience resulted in a published paper that focused on how duckweed, a small floating plant that grows in nutrient-rich aquatic environments, can be used to recover nitrogen and phosphorus from wastewater.

The experience also exposed Clack to the realm of academia, a field he hadn’t previously considered for his career. However, Clack first chose to pursue a career in industry in the industrial wastewater sector in Los Angeles, where he saw many missed opportunities for reduced water consumption and resource recovery. This observation later inspired Clack to pursue graduate studies at UCLA in environmental engineering.

“I noticed a lot of opportunities that were missed for resource recovery,” Clack said. “Not just recovering the water, but also things like biofuels, nutrients and fertilizers.”

Clack is conducting research on reclaiming potable water from wastewater while also recovering pipeline-grade methane and other biofuels that can make the reclamation process carbon negative, energy positive, and economically favorable. This research aims to reduce the carbon emissions and economic burden of water reclamation.

The approach will soon be pilot tested and if it is validated, Clack said he hopes the system will be adapted into municipal wastewater reclamation systems in the future, including the water recycling plant to be built on UCLA’s campus by 2025. READ MORE