Ferrate vs. Blue Green Algae – The real culprit isn’t just nitrogen and phosphorus, it’s ammonia.
It’s time to get serious about treating wastewater and stormwater runoff, PROPERLY, before it ends up in our surface and groundwater.
– Dr. Tom Waite, Founder, Ferrate Solutions
What we all need to know:
First, it’s important to say upfront, because there have been many questions coming to us about why Ferrate isn’t currently being used to treat wastewater, drinking water, storm water, or polluted lake and river water in Florida, that Ferrate Solutions IS IN PROCESS with Florida Department of Environmental Protection (DEP) and the newly-formed Blue Green Algae Task Force through the RFI process. They are aware of this new technology. We are waiting to hear “next steps” and will post accordingly.
Second, there’s a lot of confusion, from the media and scientists on down to the public, about the nature and role of Nitrogen in cranking up bacteria and algal blooms – which we need to get past if we are going to make any headway in solving this problem.
Some History: The State, long ago established “target” limits for phosphorus (P) in surface waters with the hope that if our waters stay below the limit, algal and bacterial blooms would also stay away. Nitrogen was not “regulated” because its environmental chemistry is a little tricky. Of course, we haven’t been able to keep the nutrient levels in our lakes, canals and coastal waters below the “suggested” limit and blooms prevail. Given the recent infusion of money (thankfully) from the Governor and Legislature, , it’s time to get serious about addressing the problem in more detail and to develop a real science + engineering-based Master Plan to control the influx of nutrients that is driving this out-of-control productivity in our surface waters.
WOULDN’T IT BE NICE IF WE COULD JUST STOP DISCHARGING NUTRIENTS INTO THE WATER???
While that’s a laudable goal, it’s not realistic to believe we can do that without treatment of contaminated water. If we are going to grow food, we need the fertilizer, and unless we all stop using the restroom, we won’t reduce the amount of domestic wastewater that we generate.
So that leaves “managing” the quality of all discharges of waste and runoff to our surface (and ground) waters. However, effective management scenarios of nutrient laden discharges require realistic, science-based water quality standards (targets) in order to be effective. Obviously, the most effective “management” scheme is to remove enough nutrients from discharges to maintain surface water nutrient concentrations below the water quality standards. And yes, this level of treatment can now be achieved utilizing the recently commercialized Ferrate technology.
But this treatment break-through is only part of the story …… Realistic, treatment goals (surface water quality standards) must be established for the major nutrients regulating growth (and blooms) of aquatic plants and photosynthetic bacteria. However, without an understanding of the various roles that different nitrogen compounds play in algal and bacterial metabolism, meaningful and effective limits (i.e. treatment goals) to productivity cannot be established for our surface waters. The challenge and need for better information on this issue was a point made very clear by Dr.’s Sullivan and Parsons, members of the Blue Green Algae Task Force, at last week’s meeting.
SO WHAT DOES THAT MEAN ABOUT NITROGEN? Unlike phosphorus, nitrogen can exist in our environment in many different forms with different valences, e.g. ammonium NH4+ (reduced, valence = -3) or nitrate NO3– (oxidized, valence = +5). This makes the chemistry complex, especially when it comes to uptake of nitrogen by aquatic plants & bacteria. All nutrients must be reduced (via enzymes) before they are transported through cellular membranes. Highly oxidized nitrogen compounds (e.g. nitrate nitrogen) must therefore be reduced before they are transported, and that process costs organisms energy. If a compound (e.g. ammonia nitrogen) is already in a reduced state, it is quickly assimilated and transported into the cells, as no expensive reduction process is required of the organism.
THIS IS IMPORTANT because ammonia is the main form of nitrogen in domestic wastewater and agricultural runoff. If you are interested in a little sourcing and back up:
“Pluses and minuses of ammonium and nitrate uptake and assimilation by phytoplankton and implications for productivity and community composition, with emphasis on nitrogen-enriched conditions” Patricia M. Glibert, et. al, Limnol. Oceanogr. 61, 2016, 165–197
This extensive study reviews the state of the art on the effect of reduced nitrogen compounds on the growth and overall ecology of algae.
Specifically, the authors conclude:
- A) The ecological effects of NH4+loading and changes in the NO3: NH4 ratio have important implications for nutrient criteria development (water quality standards), as criteria are now largely based on total N or P. Such an un-nuanced view fails to recognize that the excess of N loading, its redox state, and stoichiometric imbalances of C, N, and P have consequences for not just the quantity, but also the quality, of primary producers.
- B) Differences in productivity and ultimately species composition should result when the form of N changes.
- C) Production of some algal toxins may be different under nutrition on different forms of N. For the toxigenic dinoflagellate Alexandrium tamarense grown on NO3 , NH4 or urea, then pulsed with increases in each of the N forms, the highest cellular toxin content was found to be for cells grown on NH4
- D) In toxin-producing cyanobacteria such as Microcystis, numerous studies have shown positive, direct relationships between N availability and toxin production.
- E) It has been shown that additions of N do enhance microcystin production when sufficient P is available for growth, and in one study, addition of NH4 compared with NO3 resulted in elevated microcystin concentrations well above guidelines and sustained the bloom for a substantially longer period of time.
So when it comes to making policy and regulations related to Nitrogen, all of us at Ferrate Solutions believe the following:
Removal should NOT be all about total nitrogen
- Ammonia is the real culprit and “rules” as the best source of nitrogen for photosynthetic aquatic organisms and in this case, blue green algae.
- The presence of ammonia in the water changes plant growth rates and plant ecology.
- Ammonia stimulates the production of toxins in cyanobacteria.
- Removal should be heavily focused on ammonia nitrogen.
In summary, evidence points strongly to the importance of ammonia nitrogen in the water as the principal causative agent of blooms (when phosphorus is present). Ammonia nitrogen is the principal form of nitrogen discharged by wastewater plants and agricultural runoff.
It appears that regulations (setting standards) on ammonia nitrogen would be a useful mechanism for focusing discharge management protocols, i.e. requiring existing wastewater and stormwater treatment facilities to remove ammonia nitrogen before release. And as previously stated, Ferrate removes Total P, Total N (including ammonia nitrogen) while also serving as a disinfectant (think about no longer needing to add chlorine in treated water). Ferrate Solutions are environmentally-friendly and treatment occurs in a closed, pump-and-treat system so no chemicals are released to the environment.