Biomass conversion technologies and
LCA implementation
Davide Tonini, Brian Vad Mathiesen and Thomas Astrup
CEESA meeting,
Ålborg, 25-01-2010
Outline
Energy analysis of conversion technologies for biomass
and waste – overview
Focus on efficiency of gasification technologies
Future work: LCA implementation
Conversion technologies
Primary biomass is converted to energy carriers (syngas, biogas,
biofuels) and byproducts
Efficiencies and energy losses
Byproducts can be utilized for energy or soil amelioration
Anaerobic digestion
Crucial parameter for biogas yield:
VS content of substrate
Ash content of substrate
T and retention time (psicrophilic, mesophilic, thermophilic)
Availability of substrate (size of material, hydrolisis etc.)
Yield -----> Nm3/tonne FM
LHV biogas = 18-24 MJ/Nm3
Thermal gasification
Sub-stoichiometric thermal treatment of a fuel
Gasification agent:
Air (direct gasification)
Steam (indirect gasification)
Indicated for material with low ash content and high sintering
point (slagging problems)
Main energy parameter: Cold gas efficiency ----> energy
transferred from biomass to syngas
LHV syngas = 4 - 8 MJ/Nm3
Qsyngas  LHVsyngas
CGE 
Qfuel  LHVfuel
[1]
[2]
[3]
Biomass fate in CEESA and IDAs
Potential
technology
Biofuel to transport
methane
bio jet-fuel
biodiesel
Individual heating
Industry (1)[2]
Industry (2)
District heating plants
Decentralized CHP
Centralized CHP
Waste incineration
Total
Energy
carrier
methane
jetfuel
biodiesel
gas
gas turbines
gas
steam turbine-cogen. biomass
large boilers
gas
gasif.-SOFC-dec.
gas
gasif.-SOFC-cen.
gas
incineration
waste
anaerobic digest.
transesterification
small boilers
Carrier energy
required in IDA
2050 (PJ)1
Biomass
required in
IDA 2050
(PJ)[1]
BAU-Biomass
potential
in CEESA (PJ)
Carrier energy
potential
in CEESA (PJ)1
5.7
33.4
29.1
3.1
18.4
?
61.8
3.8
18.4
0
3.4
3.8
60[3]
73.2
73.2
6.5
28.7
41.7
44.4
251
7.9
7.9
85.8
85.8
44.4
47
5.7
0
1.6
3.1
46.5
13.5
6.5
28.7
41.7
47
194.3
According to IDAs Klimaplan (Table 21, page 90, Baggrundsrapport). When referring to gas as carrier,
the amount of biomass is recalculated based on typical efficiencies of the process considered (i.e. rapeseed to RME)
It is assumed that the energy required by industries is met both by gas and direct biomass combustion
(mainly byproducts from biofuels production)
Compared to IDAs Klimaplan the energy demand for the industry sector is decreased from 80 to 60 PJ
Conversion technologies - overview
Potential conversion
technologies
Biomass potential
Biomass
PJ
tonne
LHV (GJ/t)
Biofuels Gasif. AD Comb.
rapeseed
3.4
123,690
27.5
X
willow
0.5
33,784
14.8
X
X
grass
6.8
453,333
15.0
X
X
straw
65
4,482,759
14.5
X
X
beet top
0.2
98,039
2.0
X
animal manure
27
5,400,000
5.0
X
fiber fraction
2
147,438
13.6
X
mill residues
0.9
45,455
19.8
X
beet pulp
1.7
328,947
5.2
X
X
molasses
1.2
447,761
2.7
X
X
potato pulp
0.3
105,634
2.8
X
X
brewer's grain
0.6
141,176
4.3
X
X
whey
2.8
3,111,111
0.9
X
X
wood chips
7.7
407,407
18.9
X
X
fire wood
26
1,276,011
20.4
X
unexploited forest
17
834,315
20.4
wood pellets
2.6
127,601
wood residues
6.3
waste
47
TOTAL
219
Main byproducts generated
Selected
Byproduct 1 amount (PJ) Byproduct 2 amount (t)
X
to RME
rape meal
X
gasification
char
X
Anaer. Dig.
fibers
X
gasification
char
X
X
Anaer. Dig.
digestate
X
X
Anaer. Dig. liq. Fract. (t) 1,791,375
X
X
Anaer. Dig.
digestate
X
Anaer. Dig.
digestate
X
Anaer. Dig.
digestate
Anaer. Dig.
digestate
X
Anaer. Dig.
digestate
X
Anaer. Dig.
digestate
Anaer. Dig.
digestate
X
gasification
char
tar
X
X
gasification
char
tar
X
X
X
gasification
char
tar
20.4
X
X
X
gasification
char
tar
318,182
19.8
X
X
X
gasification
char
tar
4,700,000
10.0
X
X
X
combustion bottom ash
X
X
X
X
1.2
K2SO4
802
4.5
proteins
68,000
tar
digestate
fly ash
6.7
0
Gasification and anaerobic digestion –
energy efficiency
(PJ)
Heat (PJ)
El (PJ)
CGE[1]
Gas yield (Nm3/t)
LHVgas (GJ/Nm3)
0.5
6.8
65.0
0.2
0.07
0.23
7.79
0.06
0.01
0.05
0.66
0.01
0.93
0.85
2118
210
1896
67
0.0065
0.01974
0.0065
0.02404
Gross[2] energy in gas (PJ)
Not relevant here
0.5
1.9
55.3
0.2
1.03
0.43
0.12
0.20
0.25
0.04
0.01
0.05
0.85
0.93
beet pulp
8.6
2.0
0.9
1.7
67
3203
2833
67
0.0223
0.0036
0.0065
0.02404
2.6
1.7
0.8
0.5
molasses
1.2
0.27
0.06
67
0.02404
0.7
potato pulp
0.3
0.06
0.02
67
0.02404
0.2
brewer's grain
0.6
0.08
0.02
320 (?)
0.02404
1.1 (?)
whey
wood chips
fire wood
Forest unexploited increm.
wood pellets
wood residues
2.8
7.7
26.0
17.0
2.6
6.3
1.85
1.01
3.41
2.23
0.34
0.83
0.45
0.09
0.29
0.19
0.03
0.07
44
2704
2915
2915
2915
2833
0.01794
0.0065
0.0065
0.0065
0.0065
0.0065
2.4
7.2
24.2
15.8
2.4
5.9
Not relevant here
143
19.8
2.2
Biomass
rapeseed
willow
grass
straw
beet top
manure
fiber fraction
mill residue
waste[3]
TOTAL
[1]
[2]
[3]
0.93
0.93
0.93
0.93
0.93
CGE=Cold Gas Efficiency. It is the most important parameter to assess the energy efficiency of a gasification process
The energy content of the gas does not take into account the energy required for the plant heat/energy consumptions
Only the residual waste (after source separation) which is today used for energy purposes is here considered
121.4
Conclusion - technologies
Biomass availability is limited especially for biofuels
Need for energy crops (33.4 PJ of bio-jetfuel and 29.1 PJ of
biodiesel)
Integration of gasification and anaerobic digestion with gasfired SOFC power plant -------> estimation of energy savings
and “decreased performance” of the connected power plants
Future work – LCA
Future work: implementation of LCA by means of Simapro
and EASEWASTE (for waste)
Period: February – June 2010
LCA is Dependent on:
The choice of conversion technologies
The fate of the biomass
The scenarios
Direct and indirect LUC consequences (Lorie)
Implementation of LCA
Analysis of all energy and mass flows
Assessment of re-utilization of byproducts for energy
or agriculture purposes (also char from gasification)
Indirect Land Use Change ------> Not included in the
first assessment (further collaboration with Lorie)
Agricultural
land
Agricultural
land
Biodiesel
from
rapeseed
Agricultural
land
0.36 kt barley
8.7 kt palm
fruit
26.8 kt soy
beans
0.36 kt
carbohydrate
fodder
0.36 kt palm
meal
Palm oil and
meal
production
8.4 kt palm oil
4.8 kt soy
oil
Soy oil and
meal
production
4.8 kt soy oil
22 kt soy meal
Methanol
production
Agricultural
land
0.25 PJ rapeseed
(3.6 kt rape oil)
0.013 PJ
methanol
22 kt rape meal
1 PJ
rapesee
d
Oil milling
Catalysts
production
63 t KOH
Fertiliser
production
236 t K-fertilizer
Glycerine
production
1.39 kt glycerine
0.54 PJ
rape oil
22 kt soy
meal
22 kt animal
fodder
Esterification
0.48 PJ
RME
0.48 PJ RME
236 t catalyst
1.39 kt
glycerine
Straw gasification
1 PJ straw
73 kt straw
Straw gasification
Biochar
0.85 PJ syngas
Use-on-land
Binding of carbon in
the soil
Depletion of carbon
in the soil
Decrease of crops
yield
Wood gasification
1 PJ wood chips
Wood
gasification
Biochar
Lost
alternative?
0.93 PJ syngas
Use-on-land
Anaerobic digestion of grass
1 PJ grass
Anaerobic
digestion
1 PJ grass
Biogas purification
0.32 PJ CH4
0.1 PJ fibers
fraction
6.6 kt Animal feed
Agricultural
land
6.6 kt barley
6.6 kt barley
Anaerobic digestion of manure
1 PJ animal
manure
1 PJ
manure
Separation &
Anaerobic digestion
Biogas
purification
(3497 kt N, 867 kt P, 1746 kt K)
Fertilizer
production
Fertilizer (3497 kt N, 867 kt P, 1746 kt K)
Storage
Fertilizer (3518 kt N, 854 kt P, 2043 kt K)
Fertilizer
production
Fertilizer (2286 kt N, 854 kt P, 2043 kt K)
0.3 PJ CH4
Digestate & liquid
manure
Use-on-land
Use-on-land
1 t residual
waste
steam
Waste
refinery
Anaerobic
digestion
2 GJ biogas
0.4 t solid
fraction
Cocombustion in
power plant
5 GJ RDF
24 kg glass
Glass
recycling
24 kg glass
Resources/e
nergy
Glass
production
0.96 t liquid
fraction
water
enzymes
Residual waste
The Renaissance option
20 kg
ferrous
metals
Ferrous metals
recycling
20 kg Iron
Steel
production
10 kg
Aluminium
Aluminium
recycling
8.2 kg
Aluminium
Aluminium
production
13 kg
plastic
Plastic
recycling
11.6 kt
crude oil
Plastic
production
20 kg steel
8 kg Al
10.5 kt
plastic
Residual waste incineration
Thermal
treatment
1 tonne residual
waste
Natural gas
extraction
Natural gas
ash
Disposal in mineral
landfill
20 kg Fly ash
Disposal in salt
mine
180 kg
Oil extraction
Coal
0.21 GJ el, 0.76
GJ heat
Oil
CHP
Conclusion (remarks..) - LCA
LCA implementation is dependent on:
Biomass availability
Choice of the conversion technologies (also own decision)
Indirect LUC for cultivation of energy crops
Thank you for the
attention