E N D
1. Protecting Our WaterwaysRemoval of Nutrients from Wastewater David Rei Miller
Masters Student
Sumit Banker
PG Diploma Student
2. Nutrient Removal Research Nutrient pollution is seen as the challenge of the next decade.Nutrient pollution is seen as the challenge of the next decade.
3. Presentation Outline 1 Problem Nutrient Pollution
2 Solutions Nitrogen Removal
Biological Filter
Phosphorus Removal Active Rock Filter First… PROBLEM of Nutrient Pollution. Then… SOLUTIONS for N and P removal. My Masters project is on N removal.First… PROBLEM of Nutrient Pollution. Then… SOLUTIONS for N and P removal. My Masters project is on N removal.
4. Nutrient Pollution Groundwater
Blue Baby Syndrome NO3-
carcinogen production NO3-
Surface Waters
toxic to fish NH3
algal blooms N and P
eutrophication N and P Many of you will have seen evidence of nutrient pollution in the news. NP = Nitrogen and Phosphorus.Many of you will have seen evidence of nutrient pollution in the news. NP = Nitrogen and Phosphorus.
5. Eutrophication Nutrient enrichment
Algal growth
Decay of algae
Oxygen consumption
6. Eutrophication HB pic is eutrophication from agricultural runoff (not OWTS).HB pic is eutrophication from agricultural runoff (not OWTS).
7. Sustainability Protecting Our Waterways
drinking, recreation resource
cultural values
kaitiakitanga, legal obligations
Sustainable Technology
low energy, cost, maintenance
low environmental impact Effective wastewater treatment is needed to protect our waterways. Essential part of sustainable society. RMA reflects importance.Effective wastewater treatment is needed to protect our waterways. Essential part of sustainable society. RMA reflects importance.
8. Nitrogen Domestic Wastewater
urea, proteins, amino acids
80 mg-N/L total (from onsite)
Discharge Limits
10 mg-N/L NO2-/NO3- USEPA
30 mg-N/L total (from onsite) Hawkes Bay For OWTS resource consent in Hawkes Bay. Pressure to remove N in OWTS before disposal to land due to variability of soils, etc.For OWTS resource consent in Hawkes Bay. Pressure to remove N in OWTS before disposal to land due to variability of soils, etc.
9. Nitrogen Removal Foam Media Biofilter
biological (microorganisms)
onsite wastewater treatment
target 10 mg-N/L effluent
Key Results to Date
30 mg-N/L effluent typical
nitrification, denitrification confirmed
nitrification identified as limiting
likely limited by lack of oxygen Research project to improve current Gould system. Removal varies between sites. Effluent concs are TN.Research project to improve current Gould system. Removal varies between sites. Effluent concs are TN.
10. Septic Tank + Biofilter Hydrolysis and ammonification in septic tank.Hydrolysis and ammonification in septic tank.
11. Nitrogen Removal in Biofilter Foam media for biomass growth Good air flow properties; superior to sand filters. NH3/NH4+ to NO2/NO3- to N2. Define aerobic and anoxic.Good air flow properties; superior to sand filters. NH3/NH4+ to NO2/NO3- to N2. Define aerobic and anoxic.
12. Nitrogen Removal Sustainability Potential
no forced aeration
no addition of carbon
inert end product
But…
foam life, regeneration uncertain
electricity required (pumps, controls)
Overall N management includes reduction, planting (Gunn 04). FIRST get it out of the river, then look at power, etc. Further research.Overall N management includes reduction, planting (Gunn 04). FIRST get it out of the river, then look at power, etc. Further research.
13. Phosphorus Domestic Wastewater
detergents, various foods
5-20 mg-P/L as DRP
Discharge Limits
1 mg-P/L as TP (to bay) Brisbane
1 mg-P/L as DRP (to stream) Waipukurau
not set for onsite Amateur alchemist Brand discovered P in 1669 by heating urine in the absence of air.Amateur alchemist Brand discovered P in 1669 by heating urine in the absence of air.
14. Phosphorus Removal Active Rock Filter
physical + other mechanisms
small community treatment
can add to existing pond (or onsite)
Key Results to Date
limestone 64% P removal
steel slag 72% P removal Retrofit to pond or wetland systems (Ashhurst 2000 ppl). * explain results set-up: two media for active rock filters have been tested (shown in literature to be promising). Both show significant P removal can be achieved….Retrofit to pond or wetland systems (Ashhurst 2000 ppl). * explain results set-up: two media for active rock filters have been tested (shown in literature to be promising). Both show significant P removal can be achieved….
15. Phosphorus Removal Place after pond/lagoon (after solids have been removed).Place after pond/lagoon (after solids have been removed).
16. Phosphorus Removal Now let’s look at what’s happening in there! Different media support various mechanisms (paper).Now let’s look at what’s happening in there! Different media support various mechanisms (paper).
17. Phosphorus Removal Sustainability Potential
no energy input required
low cost
simple and “low tech” like ponds
But…
design life, loadings need research
regeneration, extraction of P needs research
No problems with heavy metal leaching have been reported in literature. Alternative is to use chemical dosing or EBPR.No problems with heavy metal leaching have been reported in literature. Alternative is to use chemical dosing or EBPR.
18. Summary Nutrient removal is essential for
sustainability of water resources.
N Removal can be achieved onsite
by foam media biofilter.
Low cost P Removal possible with
an active rock filter. CETE will research oxygen limitation in N removal, also P Removal studies with Dr Ibrahim Elmetri, formerly of UQ, 2 yrs PostDoc.CETE will research oxygen limitation in N removal, also P Removal studies with Dr Ibrahim Elmetri, formerly of UQ, 2 yrs PostDoc.
19. Acknowledgments Warrick Gould
Gould GT Systems
Technology NZ
Palmerston North City Council
Steelserv
Rock Filter Researchers Thanks to PNCC for access to pond effluent for rock filter study; other rock filter researchers included Lynaire, Sumit, Babar, Rachel.Thanks to PNCC for access to pond effluent for rock filter study; other rock filter researchers included Lynaire, Sumit, Babar, Rachel.