Manure management and processing

Fridtjof de Buisonjé fridtjof.debuisonje@wur.nl

Wageningen UR Livestock Research, the Netherlands

Rednex Bucharest, 16-17 May 2013

The Netherlands: a small country on the North Sea

450 inhabitants per km2

We work on the following themes: • atmosphere (gaseous emissions, particulate matter, low-emission animal housing systems); • soil (soil quality, water, minerals and fertilisation, pasturing, grassland and feed crops); • closing mineral cycles (animal-manure-crop cycles, manure technology).

Our research: livestock and environment

Measurements of gaseous emissions and PM

The issue: meat and fertilizer consumption rising

Manure is a valuable fertilizer….

if applied correctly and in the right quantities !

But an environmental risk in a

surpluss-situation

Europe

Asia

US Corn Belt

The densely populated coastal

regions of Asia, Africa, America’s

Challenge: a better distribution of Phosphorus !

G. K. MacDonald, E. M. Bennett, P. A. Potter, N. Ramankutty. Agronomic phosphorus imbalances across the world's croplands. Proceedings of the National Academy of Sciences, USA, 2011

And less nitrogen application....

Phosphorus and nitrogen cause nutrient enrichment

and low oxygen levels in coastal waters

EPA (US): Increasing nutrient loads in sweet and salt waters

gives increase in algal blooms worldwide…..

Effect of excess nutrients on beaches in France and

China

The Netherlands: Rapid growth of animal production after WW II

(ca. 1950 – 1980)

Increasing incomes, increasing meat consumption + export

Uncontrolled manure emissions to air and surface waters; problems

(eutrophication, acidification) from ca. 1965 onward

Manure policy adopted in 1984. Production rights (poultry & pigs) and milk

quota sets limits to animal numbers and milk production.

EU-Nitrates Directive adopted in 1991 (groundwater monitoring)

EU-Water Framework Directive adopted in 2000 (surface water quality)

Environmental improvements since the 1980’s but slowing down

2014: Mandatory manure processing and export or continuing restrictions on

animal numbers ?! A decision will be taken !

Manure production in the Netherlands

Solid poultry manure 1.400.000 tonnes/year

Pig slurry 12.400.000 tonnes/year

Cattle slurry 54.800.000 tonnes/year

Agricultural land 2.300.000 hectares...

● Surplus nitrogen 119 kg/hectare/year

● Surplus phosphate 28 kg/hectare/year

Key elements of the NL manure policy:

Control of animal numbers (pigs & poultry) and milk production

(but what will happen after abolition in 2014/2015 ?!)

Application standards for nitrogen (N) and phosphate (P2O5) from

animal manure and from chemical fertilizers

Manure application ban in autumn and winter

Mandatory low-emission storage and application methods

Monitoring of manure distribution and export (incl. weighing, GPS-

tracking and chemical analyses of N and P2O5 content of every load)

Financial support for R&D on manure management and processing

technology

Measurement of the environmental effects of the manure policy,

feedback and adjustments if necessary...

Nitrate in groundwater, EU-Nitrates Directive 1991

350 measuring points

Nitrate levels in upper groundwater in sandy,

clay and peat soils, 1992 - 2009

EU-standard:

50 mg NO3-/liter

Application limits for nitrogen (N) and phosphate (P2O5) from animal

manure (EU-Nitrate Directive / Water Framework Directive)

• Nitrogen (N) max 350 kg/ha/year (crop dependant), from animal manure & from chemical fertilizer ! • max 170 kg N/ha/year from animal manure (‘Derogation’ = max 250 kg for cattle farms with grassland)

• Phosphate application rate depending on soil phosphate condition:

55 – 100 kg P2O5/ha/year (P2O5 = P * 2.29)

• In the Netherlands the phosphate application rate is limiting >> mandatory

export and processing of manure (phosphate) !

Nitrogen efficiency of animal manures and fractions

(Chemical fertilizers have 100 % nitrogen efficiency by law !)

Cattle slurry (with/without grazing) 45/60 %

Pig slurry (on clay and peat/sand and löss) 60/70 %

Liquid fraction and muck water (‘gier’) 80 %

(also for mineral concentrate from Reverse Osmosis)

Solid cattle manure (depending on system) 30-60 %

Solid pig and poultry manure 55 %

Phosphate (P2O5) from animal manure / fertilizer 100 %

Example of calculation of fertilizer allowance

(on top of the nutrients from animal manure)

Arable land (potatoes): max. 170 kg N/ha/year from animal manure

Total N-application standard for potatoes: 225 kg N/ha/year

Phosphate application standard on arable land: 85 kg P2O5/ha/year.

Pig slurry: 7 kg N/ton and 4 kg P2O5/ton

• N: 170 : 7 = 24 ton pig slurry per hectare

• P2O5: 85 : 4 = 21 ton pig slurry per hectare Phosphate is limiting !

• 21 * 7 = 147 kg N from pig slurry, N-efficiency 60 %: 0.6* 147 = 88 kg

effective N per hectare, 225 – 88 = 137 kg N-fertilizer allowance

Slurry spraying is not allowed anymore...

Low-emission manure application is the standard

Maximum numbers of animals per hectare

(estimates)

≈ 2 dairy cows / hectare

≈ 20 fattening pigs / hectare

≈ 7 sows with piglets / hectare

A farm with 200 dairy cows needs approx. 100 hectares

A farm with 5.000 fattening pigs needs approx. 250 hectares

Not enough land ?!

Manure distribution or export or processing !

Too much pig and cattle slurry

Most livestock farms in the Netherlands produce more manure than is

allowed to be applied on their own land

Transportation of surplus manure at high cost (5-20 €/ton)

Dry poultry manure suitable for export and incineration

Pig and cattle slurry not suitable for long distance transport

Transported pig slurry: 10.000.000 tons per year

Transported cattle slurry: 7.000.000 tons per year

Slatted floors with slurry

storage underneath

Annual slurry production by NL cattle and pigs:

Dairy cattle: 25 tons per dairy cow per year

Fattening pigs: 1.2 ton per pig(place) per year

Sows with piglets: 4.3 tons per sow per year

One truck load: 35 tons...

Comparison of some slurries and broiler manure (average figures; beware of variation !)

Dry matter (%)

Org. matter

(%) N-total (g/kg)

N-NH3 (g/kg)

P2O5 (g/kg)

K2O (g/kg)

Pig slurry (fatteners) 9,0 6,0 7,2 4,2 4,2 7,2

Pig slurry (sows) 5,5 3,4 4,2 2,5 3,0 4,2

Cattle slurry 9,0 6,8 4,9 2,6 1,8 6,8

Broiler litter 61 51 30 6 17 23

Green Electricity or pellets from dry poultry manure, discussion

about sustainability....

Poultry manure incineration plant

‘BMC Moerdijk’

• 400.000 t/year, 36 MWe

• 25 % phosphate in ash > fertilizer

• Nitrogen & organic matter lost...

• Subsidized

Poultry manure pellets for export

• 80 % organic matter

• NPK 5-3-3 + Ca + Mg + S + trace elements

• Not subsidized

High water content of pig and cattle slurry...

0

10

20

30

40

50

60

70

80

90

100

Pig and cattle slurry

Water

Salts

Organic matter

Water

%

Manure legislation and anaerobic digestion:

Digestate = animal slurry, so the same rules apply !

Slurry transport with manure sampling, data registration and GPS

Manure distribution:

application only during the growing season

Slurry injection in order to prevent emissions (ammonia, smell)

Nearby if possible

Precision farming with GPS

No manure application during winter !

No manure application in autumn and winter:

covered manure storage capacity for 7 month !

Manure storage under the barn or outside the barn

Mechanical separation: screw press and decanting

centrifuge (as examples)

Low separation efficiency Cheap (€ 30.000) Low energy consumption Less maintenance Low throughput

High separation efficiency Expensive (€ 200.000) High energy consumption More maintenance High throughput

Solid fraction, high in phosphate, 25-40 % dry matter

Suitable for export, (co)composting, drying and

pelletizing or anaerobic digestion

Stable organic matter

Reduction of weed seeds and

pathogens

Suitable for transport and storage

(export)

High in nutrients N,P, K and other

(trace) elements

(Mg, Ca, S, Cu, Zn, B, etc.)

Attention for nitrogen loss during

composting (up to 60 % !)

Composting (“biothermal drying”) of solid manure

Processing solid and liquid fraction

Solid fraction (high in P)

Application as organic fertilizer

Anaerobic digestion

Drying/composting/pelletizing

Incineration (like sewage sludge)

Obstacles

Cost of drying (=energy)

High ash-content

Cu and Zn from feed

Liquid fraction (most of the N, K)

Application as organic fertilizer

Biological purification

Membrane filtration

Evaporation and condensation

Obstacles

Cost of evaporation (=energy)

Disposal of sludge /concentrates

Effluent quality (Waterboards)

Location (receiving waterbody)

Biological treatment of veal calf slurry (800.000 tons/year)

Nitrogen removal by nitrification and denitrification, phosphate is precipitated into sludge, similar to municipal Waste Water Treatment Plants

Slurry transport by pipelines to 4 regional installations

Pilot Mineral Concentrate: fertilizer and water from pig slurry

Separation Animal slurry Solid fraction (org. fertilizer)

Conditioning (VS removal)

Reverse osmosis RO concentrate (NK-minerals)

RO permeate (water)

Liquid fraction

Utilisation of nitrogen from manure surplus

(mineral concentrate from reverse osmosis)

Artificial fertilizer

Artificial fertilizer

Manure

Nitrogen from manure

Crop uptake of nitrogen (max 350 kg N/ha/yr)

Actual Desired

(170 or 250 kg N/ha/yr)

Minerals from manure surplus

Manure

Pilot plant for the production of biogas and mineral concentrate from pig slurry and agricultural byproducts

Production of NK-concentrate by reverse osmosis

Composition of mineral concentrate, example:

• RO-concentrate is a N-K fertilizer • 7.5% of Total nitrogen is organic... • Low content of P

Dry Matter g/kg 36.0

Org. Matter g/kg 15.8

N total g/kg 6.9

N NH4 g/kg 6.4

N org. g/kg 0.5

P g/kg 0.2

K g/kg 7.6

Application of mineral concentrate in potatoe crop

Pilot project Mineral Concentrate

Products from animal manure will only be allowed as a

substitute for artificial fertilizer if:

● Nitrogen efficiency comparable to common artificial fertilizer

● Volatile solids (organic matter) as low as possible (‘absent’)

● Minimal mineral content (e.g. 20 % N)

(EU-Fertilizer Directive 2003/2003)

European Commission will decide in 2014 whether Mineral Concentrate can be accepted as an EU-fertilizer

Conclusions and outlook (NL perspective):

Export of phosphorus is necessary for maintaining actual animal numbers and

animal production levels in NL,

Decreasing manure space in Germany and France,

Only dry and concentrated manure products are fit for long distance transport

(dried, composted, pelleted),

Poultry manure has the highest potential (energy & export)

Incineration of solid fraction from slurry separation is an option, the ashes can

be used as a phosphate source

Mandatory processing of pig and cattle slurry (2014 ?) must result in products

that can be exported (phosphorus !)

Please remember: groundwater and surface water are used for

the production of drinking water !