Table 1. Non-biological methods of N and P removal.
Values in italic text indicate technological limitations for use in NSSS. Values in bold text indicate areas of existing R&D opportunity.
| Method | Requirements/restrictions (Y/N) | Notes | |||||
|---|---|---|---|---|---|---|---|
| Chemical
additives? |
Other
consumables? |
Power
consumption? |
Component
fouling? |
Regeneration
possible? |
Resource
recovery possible? |
||
| Air stripping | Y* | N | Y | N | n/a | Y # | *Large quantities of base
required to raise pH. #Typically requires precipitation in sulfuric acid. |
| Breakpoint
chlorination |
Y* | Y # | Y | Y # | N # | N | *Salt addition may be
required depending on effluent quality. #Costly noble-metal electrodes are eventually poisoned. |
| Chemical
precipitation |
Y | Y | N | N | N | Y* | *Cost and processes not
optimized. |
| Hydrogel/
polymer matrix encapsulation |
N | Y* | N | Unknown # | Unknown # | Unknown # | *Assumes hydrogel cannot
be regenerated. #These technologies are not mature – requires additional R&D. |
| Ion-exchange
materials |
N | Y* | N | Unknown # | Y # | Y # | *Adsorbent must be
replaced or regenerated. #R&D opportunities in materials discovery, surface chemistry modification, and resource recovery. |
| Membrane-
based separations |
N | Y* | Y | Y # | Unknown # | Y | *Assumes membrane has a
finite lifetime and cannot be regenerated. #Membrane technologies are not mature – requires additional R&D. |