A gathering of the leaders for biological phosphorus removal and recovery
In January, the Water Environment Federation convened the James Barnard Research Forum on Emerging Themes in Biological Phosphorus Removal and Recovery. This 3-day forum paid tribute to Dr. James Barnard by celebrating his significant contributions to wastewater processing, specifically focusing on biological phosphorus removal.
Three themes emerged from the forum. First, participants set out to discuss the science behind phosphorus removal and recovery to find out how much we know and don’t know about the process. Second, the forum turned an eye toward future markets and drivers. This discussion also focused on the value proposition of phosphorus recovery, including products (phosphorus, biosolids, valuable metals), services (eutrophication prevention, meeting discharge limits), and global drivers (food products, energy to mine mineral phosphorus). Third, the forum provided an opportunity to look at a broad overview of the environmental effects of phosphorus recovery.
About James Barnard and the forum
As the developer of the Bardenpho, Modified Ludzack–Ettinger, and Phoredox processes for biological nitrogen and phosphorus removal, Barnard was instrumental in bringing these innovative technologies to water resource recovery facilities (WRRFs) around the globe. The forum, held in Austin, Texas, featured leaders in biological phosphorus (bioP) removal for invited presentations and facilitated discussions. With short presentations and panel discussions, the forum encouraged free-flowing dialogue to examine the past, present, and future of biological phosphorus removal topics and set the agenda for years to come.
Phosphorus is an essential mineral for growth. However, phosphorus runoff and deposition in water bodies can cause aquatic dead zones that choke off oxygen to plants and wildlife. This leads to a unique conundrum where there can be no life without phosphorus, yet too much has disastrous effects.
Furthermore, global supplies are dwindling, and we are facing a potential crisis if renewable sources are not developed. A balance must be struck between efficiently using phosphorus while simultaneously developing recovery techniques. Recovering biological phosphorus via WRRFs can help fill this gap, but continued research is necessary to make it more efficient, reliable and accessible to utilities of all sizes.
Bacterial populations and modeling
Current knowledge and existing gaps emerged as the first theme at the forum. Presentations dove into the microbial ecology of enhanced biological phosphorus removal (EBPR), starting
with understanding two of the most important polyphosphate accumulating organisms (PAOs) in wastewater treatment, tetrasphaera and accumulibacter. These two organisms are studied widely, but there remains a knowledge gap about them as researchers continue to try to better utilize them by fully unlocking their mechanisms.
The Microbial Database for Activated Sludge (MiDAS), a program started at Aalborg University in Denmark, aims to learn more about these and other organisms by mapping the microbial diversity present in wastewater treatment systems worldwide. Getting people talking the same language by learning more about what options are present at WRRFs can help select for the most efficient and effective microorganisms.
Likewise, models frequently are used to help optimize WRRFs, plan for upgrades, and design new facilities. However, the limitations of these models came to the forefront of the modeling discussions as presentations addressed different approaches to unlocking the process dynamics of a WRRF. Each WRRF is a unique system with specific parameters and influent; as such, there exists no one size fits all approach to modeling or treatment.
Two approaches highlighted during the forum tackled overcoming modeling challenges. One suggested modeling individual units within a system, while the other seeks to develop a predictive system relying on process metabolics. Both models are viable options and the presentations set up a further discussion on how to use information gleaned from a model and put it into practice.
The discussions highlighted one universal truth: the key to all good models is more data to better understand process dynamics. As we get to know more about the intricacies of these systems, models will be more accurate.
Forum participants also examined the value proposition of phosphorus recovery. One of the current pain points in widespread phosphorus recovery is that turning these value propositions into reality requires overcoming current technology bottlenecks and improving industry business models.
The key to success is broadening the current value potential of bioP from only recovered products to the entire ecosphere. When discussing the barriers for real-world application, several ideas were put forth. These included implementing real-time population sensing, developing cheaper and simpler instruments that can be used by utilities of any size, and incorporating phosphorus recovery in all industries such as food reduction and waste recycling. Additionally, work must be done to develop regulations and incentives that help promote resource recovery while continuing to educate the public and increase awareness about the potential value.
Overall, the tone of the session was optimistic, and attendees agreed that the research and ideas currently being developed were building a much-needed knowledge base which will soon be translated to implementation at WRRFs.
Addressing environmental effects
The forum also provided an opportunity to look broadly at the environmental effects of phosphorus recovery. Representatives from utilities and government entities who have successfully addressed phosphorus concerns in their regions provided insight on replicating their successes. All panelist agreed that clearly defining regional problems are the first step in beginning to address them; science alone can’t fix all problems. The buy in of local communities and positive public perception often drives success as much as sounds science. Without seeing a direct effect – perhaps, the project isn’t entirely local or the effects aren’t readily visual – achieving buy-in can be difficult.
One example shared the experience of the U.S. Environmental Protection Agency’s Chesapeake Bay Program. When first starting, this program, which aims to clean up the formerly polluted bay, required getting signatures on more than 400 best management practice documents from around the entire region. These 400 individual agreements combined to increase the health of the bay, but individually, they only had a small effect and local communities had to be convinced to buy-in to help the overall region.
Forum speakers recommended making the effort to translate national or regional challenges into the effects it has on your specific locality. By making it a personal issue, citizens are more likely to connect. Also, involving key, trusted members of a community can further help promote public acceptance. Overall, a clear message tackling a well-defined problem that community members can engage with is the best way to quickly and efficiently get projects completed locally.
More to come
All participants reconvened at the end of the forum to summarize and discuss the best ways to approach phosphorus removal and recovery now and in the future. Throughout the next few months, the forum’s steering committee members plan to summarize the event thoroughly and release outcome reports. They aim to capture the entirety of the forum, the current state of the phosphorus removal and recovery science, what recovery needs to look like in the next 50 years, and what research needs to be tackled to meet these needs. In the meantime, the forum’s complete, 42-page technical program can be accessed online at www.wef.org/forum.
Patrick Dube is a technical program manager in the Water Science & Engineering Center at the Water Environment Federation (Alexandria, Va.). He manages the Residuals and Biosolids Committee and the Air Quality & Odor Control Committee. He can be contacted at firstname.lastname@example.org.