Understanding a Duckweed System
in a Temperate Climate from
Harvest to Disposal
Jon Farrell (presenter) email: jonbay@gmail.com
Maureen Kesaano and Dr. R. Ryan Dupont
1st International Conference of Duckweed Research and Applications (ICDRA-2011)
Acknowledgements
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Dr. R. Ryan Dupont
Maureen Kesaano
Brett Housley
Naho Orita
Brittany Wilkes
Louis Landesman
START
Remove Contaminant by
Harvesting Duckweed
Fuel
Crop/Feed Production
Compost
Digestion or
Fermentation
Location
Wellsville, Utah
photo Wesley Davis accessed http://www.city-data.com/city/Wellsville-Utah.html
Phosphorus Cycle
Cache Valley Utah
Wellsville Municipal Sewage Lagoons
23 ha (56 acres)
Logan City Wastewater Lagoons
186 ha (460 acres)
Wellsville Municipal Sewage Lagoons
Qin
2070 m3/day (0.547 MGD)
Qout
973 m3/day (0.252 MGD)
Water loss: 54% (evaporation/seepage)
Pin=3-5 mg/L Pout=0.95 mg/L
BODin=142mg/L BODout=16mg/L TSSin=153mg/L TSSout=13mg/L
Duckweed Cover
5-6 months
(May to mid-November)
Harvesting
Laboratory Experiments
Phosphorus Removal
Field Experiments
Field Experiments
Duckweed Growth: Production
Duckweed Growth: Production
Duckweed Growth: Production
BIOMASS YIELD:
74-308 t (82-340 dry tons)/yr
(Annual – 14 day Harvests)
1% P
Solids Handling: Methane production
105 L-CH4/kg(dry duckweed)
Gas Composition = 65% methane
Solids Handling: Ethanol production
50 g-Ethanol(63mL)/kg(dry wt.) with <10% starch (as is)
100 g-Ethanol(127mL)/kg(dry wt.) with 19% starch (nutrient starvation)
photo courtesy Dr. Jong-Su Eun
Solids Handling: Animal Feed
Solids Handling: Compost to Crop
photos Mike McFarland
http://commons.wikimedia.org/wiki/File:SiphonTubes.JPG
photos Mike McFarland
Irrigate: 20-60 ha (50-150 ac)
Land apply 3084 kg-P & 15,422 kg-N
***
Crop Production:
30,000 bushels corn
390 t (430 tons) alfalfa
10,000 bushels wheat
Summary: Harvest to Disposal
Growth
Disposal
166,000 km/yr…
Harvest
2.7x106 km/yr…….…………
Nutrient
Uptake
Thank You!