2. biogas-training fertilizer management, use of … · biogas-training fertilizer management, use...

This project is part of the International Climate Initiative. The German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety supports this initiative on the basis of a decision adopted by the German Bundestag.

Michael Köttner, International Biogas and Bioenergy Centre ofCompetence (IBBK)AnkaraAnkaraAnkaraAnkara, , , , 11.07.201111.07.201111.07.201111.07.2011

1

2. Biogas-Training

Fertilizer Management, Use of Fertilizer Management, Use of Fertilizer Management, Use of Fertilizer Management, Use of DigestateDigestateDigestateDigestate –––– Closed Loop TechnologyClosed Loop TechnologyClosed Loop TechnologyClosed Loop Technology


- Direct digestate utilization- Fertilizer value- Hygiene and nutrients- Nutrient management- Ecological and economical evaluation- Digestate processing- Liquid and solid phase- Fiber and fertilizer production

Fertilizer management and use of the digestate

2


Biology – properties of different manures

Liquid manure type pH - Value C/N Properties

Cattle liquid manure 6.8 – 7 10 – 17• Good buffering capacity• Rich in methane bacteria

Pig liquid manure approx. 7 5 - 10

• Good buffering capacity• High proportion of heavy

metals (Zn 700-2000; Cu 250-760 [mg/kg DM])

Poultry liquid manure 7 – 7.3 approx. 7• Good buffering capacity• Strong sediment accumulation

Direct digestate application

3


Positive changes of liquid manure properties through fermentation

Odor reductionReduction of the odor causing substances (humid acids, Phenols, Phenol derivate)

Decomposition of organic substance

o Decomposition rates oDM: of up to 40% o The fermented liquid manure can pumped and sprayed better compared to the raw liquid manure o The agitation is reduced before the application on land

Sanitization

The degree of the sanitization depends on residence time, temperature and applied procedure

4


Positive changes of liquid manure properties through fermentation

Destroying the weed seedsThe longer the seeds in the liquid manure are exposed to the process and the higher the temperature is, the more rapidly decreases the germination capacity

Avoidance of plant corrosion

Improvement of the fertilizer value

The fermented liquid manure has a better short term N-Fertilizer effect

5


Geruchsminderung in Abhängigkeit von der Verweilzei t

0

50

100

150

200

250

10 12 15 40

Verweilzeit in Tagen

rela

tive

Kon

zent

ratio

n in

Pro

zent

x

p-Kresol

Ethyl-Phenol

Indol

Skatol

Iso-Buttersäure

Odor reduction vs hydraulic retention time

Hydraulic retention time (days)

Rela

tive co

nce

ntra

tion (%

)

6


1,00E+00

1,00E+01

1,00E+02

1,00E+03

1,00E+04

1,00E+05

1,00E+06

1,00E+07

1,00E+08

1,00E+09

GKZ EBA GCF FCF FKS

Keimart

Anzahl in K

BE

/ g

Rohgülle

Biogasgülle

93,75%

99,90%

Anlage: Laukenmann Temp.: 38°C VWZ.: 80 Tage Typ: Betonfermenter Datum: Juni 1993

99,98%

99,70%

Messung durch Institut für

Tierhygiene, Universität Hohenheim

99,98%

Reduction of pathogenic germsPlant: Laukenmann

Temp.: 38°C

HRT: 80 days

Type: Concrete digester

Date: June 1993

Row l. manure

Biogas digestate

Measurements by the institute for animal hygiene, University of Hohenheim

Germs Type

Am

ount in

KBE/g

7


Mean values of some samples from cattle liquid manure and biogas digestate – Oberlungwitz

biogas plant study case

� Cattle liquid manure

� Biogas digestate

Source: Saxony Regional Office for Agriculture FB LB, Jäkel

Kg/m

3

DM (%) Nitrogen Ammonium Phosphor Potassium Magnesium Calcium pH-value

8


Use of biogas digestate

Digestate can be spread on the fields- no hygiene restrictions with animal slurry and plant materialImproved Fertilizer - avoids nutrient losses- reduces burning effect on plants- improves flowing properties- improves plant compatibility - improves plant health- reduces germination ability of weed seeds Environmentally sound- reduces the intensity of odor- reduces air pollution through methane and ammonia- reduces the wash out of nitrate- sanitizes liquid manure- recycles organic residues (co-fermentation)- can avoid connection costs to a central sewer

5

9


S&H Umwelt GmbH & Co.

Environmental friendly (ecological) liquid manure management

Very big quantities of liquid manure lead to:

o Off Odor impacts during treatment and productiono Spreading of pathogenic germso Damage of the botanical composition and building of a typical “Liquid Manure Flora” in the available grasslando Worsen the soil propertieso Contamination of the ground and surface waters

Biogas technology can not substantially reduce liquid manure quantities.

It OFFERS HOWEVER, different solutions for this problem, thanks to its

positive energy balance from the production of biogas .

10


Liquid digestate processing and fertilization

Digestate storage

After the anaerobic treatment of liquid manure and during the storage nitrogen losses occur in form of ammonia

Digestate land application

During the application nitrogen losses can be presented in gaseous form (ammonia) and in mineral form (nitrate)

11


Land application techniquesLand application techniquesLand application techniquesLand application techniques

Fertilizer distributor tractor: strong smell and ammonia emissions, wind-sensitively

Drag hose tractor: precise fertilization, around 41% lower NH3 emissions

12


o No excessive agitation before the applicationo Deploy cooled substrate from the final storageo Spread using emission-reducing techniques (drag hose tractor, etc.),o Processing the digestate

To prevent the nitrate leaching by liquid digestate fertilization other measures, besides the type of treatment must be taken into account:

o Sufficient storage capacity (at least 6 months)o Periods of applicationo Quantity of liquid digestate (and thus N-quantity) to be appliedo Spreading technology

Measures during liquid digestate application

13


ReasonsReasonsReasonsReasons forforforfor processingprocessingprocessingprocessing digesteddigesteddigesteddigested slurryslurryslurryslurry

o Saves storage volume (liquid phase)o Surplus of nutrients or lacking area for land spreading

Export of nutrients requiredo Digestate contains 70-90 % of water

Removing water saves transport costso Reduced costs for land spreadingo Reduced environmental impacts

o Nutrients release in the liquid phaseo Reduction of volatile air pollutantso Odor reduction

14


Basic Basic Basic Basic principlesprinciplesprinciplesprinciples ofofofof digestate digestate digestate digestate processingprocessingprocessingprocessing

Physical o Liquid-solid separationo Membrane technologyo Vacuum evaporation

Chemical o Flocculation

o Precipitation (MAP, Phosphate)

o Anaerobic digestion

o Composting (aerobe)

o Activated sludge process (aerobe)

o Nitrification, denitrification

Biological

15


Processing strategiesProcessing strategiesProcessing strategiesProcessing strategies

1. Partial separation 2. Complete separation

C, P2O5, Norg

N, P

N, K

N,P,K

Elimination of P2O5 Elimination of P2O5 + N

C, P2O5, Norg

16


Applied TechnologiesApplied TechnologiesApplied TechnologiesApplied Technologies

o Liquid-solid separation

• Screw press

• Decanter centrifuge

• Solar Drying

o Membrane technology

o Vacuum evaporation

17


Liquid solid separation Liquid solid separation Liquid solid separation Liquid solid separation –––– partial processingpartial processingpartial processingpartial processing

Separation of solid contentsSeparation of solid contentsSeparation of solid contentsSeparation of solid contentsalwaysalwaysalwaysalways the the the the 1111stststst processing step!!!processing step!!!processing step!!!processing step!!!

o 20-80 % Ptot

o 10-20 % Ntot

Removal of:

plus:

o Production of compost humus balance

18


Nutrient distributionNutrient distributionNutrient distributionNutrient distribution

19


Exemplary nutrient distributionExemplary nutrient distributionExemplary nutrient distributionExemplary nutrient distribution

o Partial processing

o Centrifuge – WLV

o Goal: P2O5 elimination

Type of nutrients to eliminate leads to choice of technology/ strategy:

P2O5: partial processing

N: complete processing

Source: WLV-Service GmbH, 2006

N: 78000 kg = 100%P2O5: 40234 kg = 100%K: 42843 kg = 100 %

N: 23288 kg = 30%P2O5: 27984 kg = 70%K: 42843 kg = 39 %

N: 55217 kg = 70%P2O5: 12250 kg = 30%K: 25940 kg = 61 %

20


LiquidLiquidLiquidLiquid----solid separation solid separation solid separation solid separation ---- screw pressscrew pressscrew pressscrew press

o 15-20 % DM

o approx. 5 % DM in liquid phase

Removes:

o Simple device – often applied

o Required coarse material for efficient operation

o Wearing part: screen (depending on input matter)

Investment costs:

20.000 - 50.000 €

21


LiquidLiquidLiquidLiquid----solid separation solid separation solid separation solid separation ---- Decanter centrifugeDecanter centrifugeDecanter centrifugeDecanter centrifuge

o 30-40 % DS

o approx. 1-3 % DM in liquid phase

Removes:

o Higher removal rate

o Suitable for subsequent complete nutrient elimination

o Digestate’s properties = criterium for device selection

Investment costs:

150.000 - 250.000 €Source: www.huber.de

22


Decanter separation of the mixture digestate/ fats

Value and efficiency of nutrients and liquid manure

Source: Danish agrarian research

Liquid -solid separation - Decanter centrifuge

Raw liquid manure

Fat waste Digestate (fermented liquid manure)

Solid fraction Liquid fraction

Weight portion (%) 97 3 100 7 93

DM content (%) 5,2 41,4 4,2 33 2,3

P (kg/t) 1,2 0,3 1,3 13,4 0,3

N-total (kg/t) 4,8 1,3 4,6 11,7 4,0

NH4-n (kg/t) 3,6 0,4 3,6 3,0 3,6

Org. N (kg/t) 1,2 0,9 2,3 2,6 2,3

NH4-n portion (%) 75 28 79 26 89

Source: Hengdal fermentation gas/Danish agrarian research

Fertilizer Efficiency nitrogen (%)

Increase in value per t liquid manure €

Pig liquid manure 60 - 70 -

Digestate (fermented liquid manure) 65 – 85 0,30 – 0,60

Separated biogas digestate 80 - 90 0,60 - 1,20

23


LiquidLiquidLiquidLiquid----solid solid solid solid separationseparationseparationseparation ---- Solar Solar Solar Solar dryingdryingdryingdrying

o Water

o Partial N-losses

Removes:

o Simple technology – mainly applied for sewage sludge

o Combined utilisation of solar heat and waste heat

o Requires complex control system

Investment costs:

approx. 300.000 €

(digestate from 450 kWel. plant)

24


HeatHeatHeatHeat coupledcoupledcoupledcoupled microgasmicrogasmicrogasmicrogas turbineturbineturbineturbine in in in in combinationcombinationcombinationcombination withwithwithwith a solar a solar a solar a solar supportedsupportedsupportedsupporteddigestate digestate digestate digestate dryingdryingdryingdrying processprocessprocessprocess atatatat thethethethe Farm Farm Farm Farm atatatat Karle, Karle, Karle, Karle, FuessbachFuessbachFuessbachFuessbach, Germany, Germany, Germany, Germany

25


Complete nutrient separationComplete nutrient separationComplete nutrient separationComplete nutrient separation

Elimination of P2O5 + N

o Complex processes, requires sophisticated technology

o High energy demand

o Economically viable only at big biogas plants > 700 kWel

C, P2O5, Norg

N, P

N, K

26


Complete separation Complete separation Complete separation Complete separation ---- Membrane technologyMembrane technologyMembrane technologyMembrane technology

o Anaerobic digestion = best preparation

o Requires good removal of coarse & fibrousmaterial (DM content ≈ 1 %)

o The better AD and solids separtion were,the better performe the membranes!

Quelle:www.haase-energietechnik.de 2007

27


Example:

3-MW biogas plant

Vacuum evaporation

source

: ww

w.a

quasy

stem

s-tech

.de

Complete separation Complete separation Complete separation Complete separation ---- (Vacuum(Vacuum(Vacuum(Vacuum----) Evaporation) Evaporation) Evaporation) Evaporation

28


Complete separation Complete separation Complete separation Complete separation ---- What’s important?What’s important?What’s important?What’s important?

o High energy demand for generating pressure or heat utilisation of surplus heat??

o Digested slurry might form crusts on the device chose technology adapted to digested slurry

o Complete removal of particulate substances (> 0,2 mm) before entering membrane technology or vacuum evaporation

Inaccurate solids removal increases rate of failure

Cleaning & Repair might take days and leads to increased costs!

29


Separated material Separated material Separated material Separated material –––– and now???and now???and now???and now???� 1 substance 2-4 different material flows� Concentrated nutrients might contain high salt loads� Concentrated nutrients allow specific fertilizer mixing� Utilization on own farm (partial nutrient removal)� Marketing?� Marketing channels?� Quality assurance and control

Requires good planning & strategic partners

30


Treatment costs of animal excrementsTechnology Energy (kWh/t) Costs (€/m 3) Application

Composting of solid manure5 -50 (for

conversion with ventilation system)

12,4 – 37,2 No delimitation on farm size

Composting of poultry dung with pine cortex

n.s. 8,1 (€/t) Test stage

Anaerobic ponds low n.s. Limited

Biological treatment of pig liquid manure

16 (5,6 % DM) 6,1 Large farms

Ventilation of liquid dung 10 - 38 0,7 - 4 Extensive experience

Mechanical separation 0,5 – 4 (kWh/m3) 1,4 – 4,2 Extensive experience

Incineration of chicken dung production 18 (€/t) > 130.000 fatlings

Evaporation and drying process of chicken dung

30 (kWh/m3 H2O) > 2,3 Test stage

Additives with pig liquid manure production 0,5 – 1 (€/animal)

Routine

31


The total costs for a decanter separation are about 1,- € per t. according todata of a Danish biogas manufacturer. This price in Denmark is profitablefor many large cattle farmers.

A further separation in the evaporator is more expensive (approx. 3.40 €per t). This expenditure should be paid back by saved transport costs andby a better utilization of fertilizer as well as by the improved spreading.

Long distances transportation of manure for the fraction which cannot beused in the surroundings of the enterprise would be profitable

Economic value of digestate is indicated either as 10 € per LU per year orrelated to the nutrients also

55 €/ t N, 56 €/ t P,28 €/ t K.

Treatment costs

32


Fertilizer value inprovement:

In areas where P2O5 is not required, the one step treatment and external transport make sense and could be profitable.

Partial separation - profitability

Nitrogen Phosphate Potassium

Cost of nutrients (€/kg) 0,60 0,45 0,35

Nutrients

Amount C1

(kg/t)

Value C1

(€/t)

Amount C2

(kg/t)

Value C2

(€/t)

∆ Value C2 –C1

(€/t)

N 9,69 5,81 11,5 6,90 1,09

P2O5 4,97 2,24 13,82 6,22 3,98

K2O 5,29 1,85 8,35 2,92 1,07

Σ = 6,14

33


ConclusionConclusionConclusionConclusion

o Nutrients = problem (surplus) nutrient separation & export might be the only solution

o But: calculate carefully (expensive technolgy) and be aware that you might need to market nutrients

o Also: which nutrients do you need to get rid off – where are they?(nutrient distribution between liquid and solid phase)

o Complete nutrient removal is only viable at big biogas plants - not for plants < 1 – 1,5 MW

o Rising demand and increasing sizes of biogas plants might lead to decreasing technology prices

34


Thank you for your attention!

35

Turkish-German Biogas ProjectDeutsche Gesellschaft fürInternationale Zusammenarbeit (GIZ) GmbHAnd Sokak No: 8/1106680 Cankaya/Ankara, TURKEY

T +90 312 466 7056T +49 6196 79830 007E [email protected] www.giz.deI www.biyogaz.web.tr

Author:Michael Köttner, International Biogas and BioenergyCentre of Competence (IBBK)

2. biogas-training fertilizer management, use of … · biogas-training fertilizer management, use...

Documents