Biogas production from

Jatropha presscake

Guillaume Beduneau and Floris

van den Hooven

Introduction - Internship at ITB

• 6 months internship at ITB Teknik Kimia

faculty, biofuel department

– Study background: Environmental Science at

Avans University Breda, The Netherlands

• Topic of internship: Digestion of Jatropha

C. presscake

– Improvement of the utilization of Jatropha C.

and asset increase for the farm/plantation

Research questions

• “Can Jatropha crude oil production be

at the same time competitive with the

global Biodiesel market, profitable for

the Indonesian producer and

environmentally sustainable?”

• “What can bio-digestion contribute to

the sustainability of Biodiesel

production from Jatropha C?”

Research setup

• Digestion of Jatropha C. presscake in 2

biodigesters

– Large Biodigester (1,5 m2)

– Experimental biodigester (22 liter)

• Operating small scale electrical

engine(500W) and gas burner on

produced biogas

– Measuring energy produced

Research Setup

• Determining additional value of bio-

digestion by calculation money value of

produced electricity/biogas

• Developing a logistic which will allow the

trading of wastes for biogas production

(deal with resistances from society)

• Determining additional “non-financial”

assets gained from Jatropha production

System of Jatropha production

Bio

-die

sel f

acto

ryB

io-d

iese

l fac

tory

Far

mF

arm

Jara

k se

eds

Seeds

Fertilizer

Labor

Energy

Labor

Energy

raw

veg

etab

le o

ilP

ure

vege

tabl

e oi

l

biog

as

Electricity

biogas

Hea

t

Digested sludge

(Fertilizer)

Bio-diesel

Jara

k m

ill

digestion

Electricity

generation

Gas

combusti

on

Bio-diesel

production

Vegetable

oil

treatment

Jatropha

Production

Expelling

(primary and

secondary

expelling)

farmer

company

The yellow box displays the focus

of our research

Today’s topic

• Biogas production from Jatropha C.

presscake

– Reasons for biogas production from Jatropha

C. presscake

– Results of the research so far

– Adaptation of digesting bacteria to

Jatropha.C.

– Expectations for future experiments

Reasons for biogas production

from Jatropha C. presscake

• 1000kg of harvested biomass will produce

– 650kg of fruit coat

– 245-280kg of residue

– 70-105kg of extracted oil (depends on the

expeller extraction capacity)

So 7w%-10,5w% of the harvested biomass will

be sold as vegetable oil.

Energy extraction from harvested

biomassweight

(kg)

energy content

(MJ/kg)

total energy

(MJ)

% energy

extraction

Harvested

biomass 1000 21.2 21200 100%

oil extracted

~30% of the

seeds weight 105 40 4200 20%

oil extracted

~20% of the

seeds weight

70 40 2800 13%

Up to 87% of the energy in Jatropha is wasted!

www.jatropha.de/Journal/Henning-paper.pdf

Application of bio-digestion to

residue

• One of the most interesting characteristic

of the biodigestion is the fact that this

process extracts energy while maintaining

the fertilizing capacity of the residue.

• Carbon conversion of 80-95% of carbon

weight (J. Visser e. a., Ingenia 2007)

Energy extracted by bio-digestion• 1000 kg residue

– Expected biogas production: 780 m3 ~ 835 kg

– LHV biogas = 18-22 MJ/kg

– Total energy extracted ~15 – 18,5 GJ

weight

(kg)

energy content

(MJ/kg)

total energy

(MJ)

% energy

extraction

Harvested

biomass 1000 21.2 21200 100%

oil extraction

=30% 105 40 4200 20%

oil extraction

=20% 70 40 2800 13%

Biogas from

residue 200 18-22 3600-4400 17-21%

So according to these expectations the energy extraction is doubled by

using biodigestion.

Results – Problems with running

bio-digester on Jatropha mill

• Observed failure to produce biogas

– pH = 5,5 (normally > 7 in a working anaerobic

digester)

– Methanogenic bacteria fail to produce biogas,

buildup of acid

• Possible reason for failure

– Jatropha presscake was added to the digester

in a too early stadium, methanogenic bacteria

failed to adapt to Jatropha (Toxins)

Bacterial adaptation to Jatropha.C

• In general

– Manure digestion works with a volume ratio of

50% fresh manure and 50% water.

– Jatropha digester works whit ~10% of

Jatropha.C and ~90% manure mix (same ratio

of dry matter in a volume of substrate)

• At the moment

– The experimental biodigester works whith

35% manure, 1,5%Jatropha.C and 63,5%

water.

Biogas production at the moment

historic experimental digester

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

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10

0

20

0

30

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10

00 T (h)

(lit

re/h

ou

r)

Gas flow (litre/h)

4vol% Jatropha

23vol% Manure

73vol% Water

pH 5.5

1,5vol% Jatropha

35vol% Manure

63,5vol% Water

pH 7.5

Expectations for further

experiments

• Achieved to adapt the bacteria

– Step by step the percentage of Jatropha.C will be increased up to the target of 10w%.

– At each step, the evolution of the biogas production will allow to evaluate the real energy extraction capacity of biodigestion.

• Burn the biogas.

– By using a gas stove and an electric generator it will be possible to measure the complete energy balance of the system.

Thank you for your attention