Advancing the water-energy-nutrient nexus in wastewater treatment plants of the future requires utilizing proven and emerging approaches

By Samuel Jeyanayagam, PhD, PE, BCEE, Vice President, CH2M HILL

Dr. Samuel Jeyanayagam, along with co-authors Wendell Khunjar and Ronald Latimer of Hazen and Sawyer, P.C. will present their paper “Closing the Loop- Strategies for Nutrient and Resource Management in Cities of the Future” on Tuesday, July 30 at 9:10 am in Session 9., during the 2013 WEF/IWA Nutrient Removal and Recovery Conference in Vancouver.  Dr. Jeyanayagam is also co-author of “Assessing Extractive Nutrient Recovery as a Viable Nutrient Control Alternative” which will be presented by Wendell Khunjar on Tuesday, July 30 at 2:30 pm in Session 11. 

Substantial global population growth and the rapid increase of people living in urban areas are adversely affecting climate change, rate of biodiversity loss, and nutrient cycles, among other planetary boundaries. Efficient resource (water-energy-nutrients) management has become a necessary component of any sustainable decision paradigm that seeks to reverse these trends. While leading-edge technologies are being developed for this purpose, it is necessary for the water industry to introspectively assess successes and failures with a view to prioritizing resources for innovation.

Nutrient recovery has emerged as an attractive option for managing nutrients in wastewater. Since the recovered products have valuable secondary uses, this process can potentially allow plants to generate alternative revenue streams to offset operation and management costs. Although our industry has a general awareness of the benefits of nutrient recovery, a clear path forward to wider implementation is lacking due to the dearth of technical and economic data. Our presentations will highlight information generated by the on-going Water Environment Research Foundation study aimed at filling the knowledge gap.

Energy contained in wastewater and solids is significantly higher than the energy required for treatment. Hence energy neutrality is an achievable goal and is being successfully pursued by implementing alternatives that include increased energy (methane gas) production and reduced energy consumption by the integration of emerging concepts such as anaerobic ammonia oxidation (ANAMMOX).

Based on the philosophy that all water is good water and there is only one water cycle, the industry approach to water management needs to change to incorporate integrated strategies across the entire water cycle (drinking water/stormwater/used water). This integrated resource management approach recognizes the concept of ‘fit-for-purpose’ use. Singapore has been an early integrator of this concept and can serve as a guide to other cities.

Achieving sustainable and livable cities of the future hinges on the ability to critically evaluate existing conditions and leverage site-specific opportunities to deliver optimal environmental, societal and economic benefits. Learning more about how leading-edge technologies are currently being deployed will be crucial to identifying future directions for accelerating the innovation cycle.

Our presentations will review key features of the wastewater treatment plant of the future, discuss proven and emerging approaches, outline lessons learned using case studies and discuss practical barriers to advancing the water-energy-nutrient nexus and how they can be overcome.

Dr. Jeyanayagam, a nationally-recognized wastewater treatment expert, has over 32 years of consulting and academic experience and has worked on projects in three continents. His areas of expertise include nutrient removal/recovery, biosolids processing, and disinfection. He has been exposed to all facets of a project including master planning, alternative evaluation, process design, start-up assistance, process optimization, and operator training. Additionally, Dr. Jeyanayagam has written and presented over 150 papers and co-authored over 20 Water Environment Federation (WEF) publications. He plays a leadership role in WEF as Chair of the Municipal Wastewater Treatment Design Committee (the largest WEF committee) and as member of the editorial board of the Water Environment Research and Water Environment & Technology journals.