Reducing phosphorus losses from agriculture:
Mitigation options and nutrient recovery from manure
Oscar Schoumans
(Alterra Wageningen UR)
Workshop resource recovery
25 June 2015, Milwaukee, Wisconsin
Content
1. Introduction
2. Mitigation options: implementation EU Directives
3. Closing the nutrient cycle: nutrient recovery
4. Conclusions
Source Apportionment
Water Quality
P = Losses from Point Sources
S = Losses from Scattered dwellings
N = Losses from Natural areas
D = atmospheric Deposition on freshwater
A = Agricultural losses
R = Retention in lakes and rivers
Eurtrophication status Western EU:
> 70% classified as less than good
Dutch P surplus & Degree of P saturation
Dutch P surplus agricultural land (1970 -2010)
60
Leaching
o-P concentration
(mg L-1 P)
kg P2O5 per ha (* 0.9 ==> lbs/acre)
50
40
30
20
10
0
1970 1986 1990 1995 2000 2005 2010
DPS (%)
CBS-Stat, 2012
P accumulation in soils
----------------------------------------------Phosphate Sorption Capacity of the soil
= Degree of Phosphate Saturation (DPS)
Schoumans &
Chardon, 2014
Content
1. Introduction
2. Mitigation options: implementation EU Directives
3. Closing the nutrient cycle: nutrient recovery
4. Conclusions
EU Directives (nutrients) & Implementation
Water
Waste framework
Bathing water Directive
Dangerous substances
Groundwater Directive
Nitrates Directive
Water Framework Directive
Marine Strategy Framework Directive
75/442/EEC amended by 91/156/EEC
76/160/EEC amended by 2006/7/EC
76/464/EEC = 2006/11/EC
80/68/EEC
91/676/EEC Action Plan (Manure & Fertilizer Act)
2000/60/EC River Basin management Plans
2008/56/EC
Air
IPPC directive
Air quality framework directive
Air quality
National Emissions Ceilings directive
Soil & Landscape
Forthcoming Thematic Soil Strategy
Currently, soil strategy
Nature
Conservation of wild birds
Conservation of Natural Habitats
96/61/EC
96/62/EC
1999/30/EC
2001/81/EC
COM(2006) 232
Annex IV of R1782/2003
79/409/EEC
92/43/EEC
Nitrate Directive: Dutch Action Plan
Phosphate application standards (kg P2O5 ha-1)
Third AP
2006
2009
2010
Fourth AP
2011 2012
2013
Fifth AP
2014 2015
Grassland
Soils with high phosphate levels
Phosphate-neutral soils
Soils with low levels of phosphate
110
110
110
100
100
100
90
95
100
90
95
100
85
95
100
85
95
100
85
95
100
80
90
100
Arable land
Soils with high phosphate levels
Phosphate-neutral soils
Soils with low levels of phosphate
95 (85)1
95 (85)
95 (85)
85
85
85
75
80
85
70
75
85
65
70
85
55
65
85
55
65
80
50
60
75
Dependent on soil P status
100
Yield90
80
70
60
50
40
30
20
10
0
0
5
10
15
20
25
Soil P content
30
35
40
45
100
P loss
Yield90
Apply less P
80
than P removal
70
by harvest
60
Target
zone
50
40
Apply more P
than P removal
30
by harvest
20
10
0
0
5
10
15
20
25
Soil P content
30
35
40
45
Wisconsin: Interpreting Soil Test P
(Bray P1)
Source: Nutrient application guidelines for field, vegetable and fruit
crops in Wisconsin (Laboski & Peters, 2012)
(Bray P1-test)
Source: http://ipcm.wisc.edu/blog/2011/01/average-soil-testphosphorus-and-potassium-levels-decline-in-wisconsin/
DRP runoff water in relation to soil P status
topsoil (0-2 cm)
Source:
http://www.soils.wisc.edu/extension/materials/P_Basics.pdf
(L.G. Bundy, Dept. of Soil Science, University of Wisconsin)
100
STARTING POINT FOR IMPROVEMENT WATER QUALITY
P loss
Yield90
Apply less P
80
than P removal
70
- Setting target for “optimal STP”
by harvest
60
Target
zone
50
40
- Maximal application standards depending on STP level
Apply more P
than P removal
30
by harvest
20
10
SOURCE ORIENTED APPROACH
0
0
5
10
15
20
25
Soil P content
30
35
40
45
EU-COST869: 80 additional measures for WFD
Farming System
Global budget
Nutrient & livestock
management
Measures at farm system:
- Feed with a lower P content or higher amount of
digestible P
- Buy less mineral fertilizers due to fields with a high
soil P status
Schoumans et al., 2014
http://www.cost869.alterra.nl/
EU-COST869: 80 additional measures for WFD
Farming System
Global budget
Nutrient & livestock
management
Field System
Nutrient distribution
in space and time
Crop & soil management
Measures at field system:
- 4R Stewardship
Right amount, Right source, Right place & Right time
- Type of soil tillage (no tillage, direct drilling, shallow
cultivation, ploughing) PP & DRP
- Avoid artificial losses: compaction, tramlines, take
care of feeding stock places / cracked soils etc.
- Cover crops and crop rotation
Schoumans et al., 2014
http://www.cost869.alterra.nl/
EU-COST869: 80 additional measures for WFD
Farming System
Global budget
Nutrient & livestock
management
Field System
Nutrient distribution
in space and time
Crop & soil management
Measures in the landscape & hydrological system
- Hydrological and hydraulic measures to change
water flow (e.g. controlled drainage)
- Blocking & controlling runoff/erosion (e.g.
grassed waterways)
- Land use changes
Landscape and
Hydrological System
Transfer & buffer capacity
Water, land use & landscape
management
Schoumans et al., 2014
http://www.cost869.alterra.nl/
EU-COST869: 80 additional measures for WFD
Farming System
Global budget
Nutrient & livestock
management
Field System
Ecological System
Critical loads
Surface water management
Measures besides and in water systems
- Re-meandering of brooks
- River & lake restoration
- Buffer strips, buffer zones, wetlands between
agricultural areas and waterways
Nutrient distribution
in space and time
Crop & soil management
Schoumans et al., 2014
http://www.cost869.alterra.nl/
EU-COST869: 80 additional measures for WFD
Farming System
Ecological System
Critical loads
Global budget
Nutrient & livestock
management
Surface water management
Many options to
apply additional
measures to improve
suface water quality
Field System
Nutrient distribution
in space and time
Crop & soil management
Landscape and
Hydrological System
Transfer & buffer capacity
Water, land use & landscape
management
Schoumans et al., 2014
http://www.cost869.alterra.nl/
Content
1. Introduction
2. Mitigation options: implementation EU Directives
3. Closing the nutrient cycle: nutrient recovery
4. Conclusions
Main manure issues: The Netherlands
1. Nitrate Directive: application of manure max 170 kg N /ha
Derogation farms with > 80% grassland: max 230 kg N / ha
Consequence: export of manure and buying of mineral N
2. Dutch legislation 2015: intensive livestock areas 50% of the
farm P2O5 surplus need to be processed or exported
outside Dutch agriculture
Strategy: Recovery of N and P from manure, less export of
manure (OM) and reuse the recovered minerals as chemical
fertilizer or as secondary resource for industries.
Production of mineral NK concentrate
(example)
End products
Mineral concentrate
Liquid N-K fertiliser
NH4-N ≥ 90%
Ratio N-P2O5 ≥ 15
Solid fraction
P fertiliser
Organic N fertiliser
Soil conditioner
N eff MC ≈ N eff Ammonium Nitrate
Permeate
(water)
Pilot plant: P recovery from pig slurry
Size flexible
separator
Precipitation
system
Liquid fraction
Solid fraction
products
Mg phosphate
Ca Phosphate
Liquid fraction with
a low P content
Solid fraction with
a low P content
Phosphate
preciptates
Secundary
resources
NH4
solution
N-stripper
Manure with a reduced
P (and N) content
Crop
required
N-P
adjusted
manure
Concluding remarks & perspective
100
1. Source oriented P approach: need to
set agro-environmental STP
P loss
Yield90
80
70
60
Target
zone
50
40
30
20
10
0
0
5
10
15
20
25
30
35
40
45
Soil P content
2. Many options to reduce P losses from
agricultural land
Farming System
Ecological System
Global budget
Critical loads
Nutrient & livestock
management
Surface water management
Field System
Landscape and
Hydrological System
Nutrient distribution
in space and time
Transfer & buffer capacity
Crop & soil management
3. Mineral recovery from manure is
needed to close the mineral balance
and make use of valuable components
of manure as secondary resource
Size flexible
separator
Water, land use & landscape
management
Liquid fraction
Solid fraction
products
Mg addition
Acid addition
Filter
Ca-base
Filter
Phosphate
preciptate
Precipitation
system
Filter
Liquid fraction with
a low P content
Solid fraction with
a low P content
NH4
solution
N-stripper
Manure with a reduced
P (and N) content
Thank you for your attention
Crop
required
N-P
adjusted
manure