Stony Brook University Professor Patents Groundbreaking Water Quality Sensor
A new patent awarded to Stony Brook University Associate Professor Qingzhi Zhu in the School of Marine and Atmospheric Sciences marks a significant leap forward in environmental monitoring.
The innovative sensor system offers an unprecedented ability to simultaneously detect critical nitrogen compounds nitrate/nitrite and ammonium in water in real-time. This breakthrough promises to revolutionize how wastewater treatment and septic systems are monitored, providing immediate insights into water quality and protecting public health and ecosystems.
Stony Brook’s Research Environment
Zhu credits Stony Brook University as a vibrant hub for collaborative, impactful research, a fact underscored by his latest achievement. “The university plays a crucial role in advancing solutions for urgent environmental issues,” said Zhu, highlighting the institution’s commitment to fostering innovative technology development and its commercialization. The university’s robust research infrastructure, including state-of-the-art facilities like the New York State Center for Clean Water Technology (CCWT), Aller Laboratory and well-equipped machine shops, provides invaluable support to researchers.
Zhu specifically praised SBU’s collaborative spirit, noting extensive discussions with colleagues from various departments and centers. The project also received crucial financial backing from funds like the State University of New York (SUNY) Technology Accelerator Fund (TAF), CCWT (NYSDEC), and the US EPA, which supported sensor improvement, ISO 14034 verification and pilot testing. This collaborative and well-supported environment within Stony Brook and across SUNY is key to translating academic research into real-world solutions.
The Critical Significance of Real-Time Nutrient Monitoring
This patented technology directly addresses one of America’s most widespread environmental challenges: nitrogen pollution. Traditional water quality monitoring methods are often slow, relying on manual sample collection and lab analysis that can take days or weeks. This delay means that by the time contamination is detected, significant environmental damage or health risks may have already occurred.
Zhu’s sensor changes this paradigm by providing immediate, real-time data. Crucially, this is the first sensor capable of simultaneously measuring both nitrate and ammonium in one device, a significant advancement as previous solutions lacked this combined capability and were not suitable for the challenging conditions of wastewater systems. “If something happened in the system, that means it happened a month ago already,” Zhu explained about conventional methods. “But [my] sensor can tell you immediately when that happened.”
This immediacy is vital for identifying system malfunctions, preventing prolonged exposure to contaminants, and enabling rapid intervention. For instance, a sensor installed in Southampton detected a significant spike in nitrogen after a holiday weekend, immediately alerting the homeowner to an aeration pump failure, which was then promptly addressed.
Nitrogen and ammonium pollution, particularly from traditional cesspools and septic tanks, can lead to serious health issues, and high nitrate levels in drinking water are a concern, especially on Long Island where groundwater is a primary source. Beyond human health, excess nitrogen in coastal areas contributes to harmful algal blooms (HABs), which produce toxins that devastate aquatic ecosystems. By enabling continuous, accurate monitoring, this technology empowers municipalities and individual households to proactively manage water quality, protecting both human health and the environment. The sensor’s self-calibration and self-cleaning features further enhance its reliability and reduce maintenance needs, making it suitable for harsh field environments and long-term deployment.
Professor Zhu’s Pioneering Contributions
Zhu’s research career has consistently focused on the development of chemical sensors for in-situ study of elemental cycling and biogeochemical reaction dynamics, particularly in marine sediments. His work on this patent is a natural evolution of his long-standing commitment to creating practical tools for environmental analysis. He has spent years developing various sensors, including optical planar sensors for 2-dimensional chemical distribution in marine environments, measuring dissolved oxygen, pH, pCO2, and hydrogen sulfide.
His involvement with the EPA Advanced Septic System Nitrogen Sensor Challenge, which he joined in Phase 2, spurred the development of this specific sensor. Recognizing the critical need for a combined nitrate and ammonium sensor that was commercially unavailable and suitable for tough wastewater environments, Zhu rose to the challenge. His sensor was the only one to pass all phases of EPA field testing, including one-week, one-month, and six-month ISO 14034 verification, earning him an EPA award in 2020. This success is a testament to his expertise in environmental analytical chemistry and his ability to overcome significant scientific and engineering hurdles, such as ensuring data accuracy in harsh conditions and preventing sensor clogging.
Looking Ahead: The Future of Environmental Sensing
The patented technology is currently undergoing pilot testing in residential homes and public schools on Long Island, as well as with municipal wastewater treatment plants. Zhu expressed immense gratitude for the support from the Stony Brook Office for Research and Innovation and Intellectual Property Partners, which played a crucial role in the patent process. He sees a tremendous market potential for this kind of in-field nitrogen sensing, with significant potential for commercialization to bring this vital technology to a wider audience and address environmental challenges on a broader scale.
Looking to the future, Zhu is most excited about developing sensors for Per- and polyfluoroalkyl substances (PFAS), often called “forever chemicals.” He notes the extremely low regulatory standards for PFAS in drinking water (e.g., 4 parts per trillion), which current analytical approaches struggle to detect. Developing a sensor capable of measuring PFAS at such minute levels would be a “game changer” and is his next major goal, with a proposal already submitted to the SERDP program of the Department of Defense. This ongoing pursuit of innovative sensing technologies underscores Zhu’s dedication to addressing the most pressing environmental challenges of our time.