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2012 NWRI Clarke Prize Conference
Research and Innovations in Urban Water Sustainability
Recovery of Nutrients
Friday, November 2, 2012James L Barnard, Ph.D., D.Ing. h.c. BCEE, WEF Fellow
World Population Growth
10,000 BC……5 millionYear 1 ……….. 250 million1800……………1 billion1930…………...2 billion1960…………...3 billion1975………..….4 billion1987………..….5 billion2000…………...6 billion
TodayBillion
Today
6.9Billion
Population Structures by Age and Sex, 2005 Millions
300 100 100 300300 200 100 0 100 200 300
Less Developed Regions
More Developed Regions
Male Female Male Female
80+ 75-79 70-74 65-69 60-64 55-59 50-54 45-49 40-44 35-39 30-34 25-29 20-24 15-19 10-14
5-90-4
Age
Source: United Nations, World Population Prospects: The 2004 Revision, 2005.
Age Distribution of the World’s Population
0%
10%
20%
30%
40%
50%
60%
1950 1990 2030
Within 2035 60 % of the global population will live in cities
World Watch Institute 2007: > 50 % is already living in urban areas
Urbanization in the world
Foreign Policy – May/June 2011
As the new year begins, the price of wheat is setting an all-time high in the United Kingdom. Food riots are spreading across Algeria. Russia is importing grain to sustain its cattle herds until spring
grazing begins. India is wrestling with an 18-percent annual food inflation rate,
sparking protests. China is looking abroad for potentially massive quantities of wheat
and corn. The Mexican government is buying corn futures to avoid
unmanageable tortilla price rises. the U.N. Food and Agricultural organization announced that its food
price index for December hit an all-time high.”
Other salient information
219,000 more mouths to feed every night US & Canada supply 2/3 of surplus food US now use 40% of grains for bio-fuel The world food safety net has evaporated Food production in some countries rely on
water bubbles Once bubbles are depleted these would become
grain importers Increased affluence requires more water and nutrients Increasing cost of fertilizers
BNR
Possible Resource RecoveryCooling Towers
Potable Water
Heat Recovery
Composting
Irrigation
Used Water
UrineSeparation
PowerProtein Recovery
Gas
Fertilizer
Nitrification
Nitrifyingbacteria
Ammonification
The Nitrogen Cycle
Decomposers(aerobic andanaerobic bacteriaand fungi)
Ammonium (NH4+) Nitrites (NO2
‐)
Nitrates (NO3‐)Nitrogen‐fixing
bacteria inroot nodulesof legumes
Precipitation
Plants
Nitrogen‐fixing soil bacteria
Assimilation
Nitrogen in atmosphere (N2)
Denitrifyingbacteria
Nitrifying bacteria
Recovery of Nitrogen
Pre-industrial revolution, many animals fewer people – manure used as fertilizer
Post industrial revolution, fewer animals more people Malthus wrote thesis “Essay on principle of
population” predicting mass starvation - Rwanda Discovery of Haber-Bosch process to fix nitrogen
from the atmosphere for munitions saved the world -BUT IT CONSUMES MORE THAN 1% OF ALL ENERGY AND OF NATURAL GAS
Every kg produced needs 12 kWh or energy as natural gas and power.
Opportunities at wastewater treatment plants
Ion exchange was proposed in the late 60ties for removing and capturing of ammonia – not successful
Nitrification/denitrification returns nitrogen to atmosphere but remains most cost effective
Ammonia in return streams can be captured byStripping and captureStruvite formationComposting
Removed with phosphorus
Ammonia Stripping and capture from return streams - Oslo Norway From Evans 2009
HNO3 used for
absorption
Nitrogen recovery
Only viable if less energy is used than fixing Nitrogen from the atmosphereHaber-Bosch process uses about 12
kWh/kg nitrogen fertilizer
`
The Local Phosphorus Cycle
PlantResidues
AnimalManures
and Biosolids AtmosphericDeposition
MineralFertilizers
OrganicPhosphorus• Microbial• Plant residue• Humus
Immobilization Soil SolutionPhosphorus• HPO4
‐2
• H2PO4‐1
Plant Uptake
Leaching(usually minor)
OrganicPhosphorus(CaP, FeP,MnP, AIP)
MineralSurfaces
(Clays, Fe andAI oxides,carbonates)
Runoff anderosion
Primary Minerals(Apatite)
ComponentInput to SoilLoss from Soil
Mineralization
Dissolution
Precipitation
Adsorption
Weathering
Desorption
Crop Harvest
Historical Sources of Phosphorus Fertilizer
A brief history of phosphorus: From the philosopher’s stone to nutrient recovery and reuse K. Ashley ,D. Cordell, D.Mavinic –Chemosphere 84 (2011) 737–746
Future Scenarios
Towards global phosphorus security: A systems framework for phosphorus recovery and reuse options D. Cordell, A. Rosemarin, J.J. Schröder , A.L. Smit - Chemosphere 84 (2011) 747–758
Asimov on Chemistry
“We may be able to substitute nuclear power for coal power, and plastics for wood, and yeast for meat, and friendliness for isolation, but for phosphorus there is neither substitute nor replacement.” Isaac Asimov
Using corn for bio-fuel production
With 40% of the grain crop going to bio-fuels for no gain in energy and enormous subsidies
Urine recovery Urine contains 70% to 80% of
the Nitrogen and Phosphorus in domestic wastewater
When urine is separated and stored ammonia is hydrolyzed and the pH goes up
Within a few weeks the urine is totally free or pathogens
Research underway to recover struvite
Excess ammonia recovered with stripping and production of ammonia sulphate