Biomass As A Renewable Energy Source: The case of Converting Municipal Solid Waste (MSW) to Energy

Biomass As A Renewable Energy Source:
The case of Converting Municipal Solid Waste
(MSW) to Energy
Baharuddin Bin Ali
[BSc(Hons) PhD(Leeds), FIEM, PEng]
Puri Pujangga
Universiti Kebangsaan Malaysia (UKM)
National University of Malaysia
16TH June 2014
7th Asian School on Renewable Energy
President Yayasan Mahkota

Baharuddin Bin Ali
7th Asian School on Renewable Energy, Puri Pujangga UKM, Malaysia, 16th-20th June 2014
Sypnosis
The paper describes the importance of biomass
as a source of renewable energy. Biomass
materials have greatest potential to be
processed as feedstocks in bio-energy
production or as fuels in combustion,
gasification and pyrolysis systems. It discusses
various methods of preparing the biomass
materials. It identifies various applications and
focus areas of research and development in
handling, storage of biomass.
2

Baharuddin Bin Ali
Biomass as Energy Source : Pros and Cons
• Pros:
• Domestic benefit
• Reduced trade deficit
• Create jobs
• Strengthen rural economies
• Local raw materials
• Renewable resources
• Carbon cycle to reduce build up
of greenhouse gases
• Technology improvements
should continue to reduce costs
3
Cons:
• Lower energy density
• Solids difficult to handle
• High water content
• Competing uses as high value food
stuff
• Symbiotic relationship —producers &
users
• Commercial Issues
• Biomass feedstock, availability, &
cost
• Suitable sites
• Production technologies
• Qualified owner‐operator
• Project financing

Baharuddin Bin Ali
Clean Air Act & Amendments
• Series of Clean Air Acts
• Air Pollution Control Act of 1955
• Clean Air Act of 1963
• Air Quality Act of 1967
• Clean Air Act Extension of 1970
• Clean Air Act Amendments in 1977 & 1990
• 1977 Clean Air Act amendments set requirements for "substantially similar
gasoline“
• Oxygenates added to make motor fuels burn more cleanly & reduce
tailpipe pollution (particularly CO)
• Required that oxygenates be approved by the U.S. EPA
• MTBE & ethanol primary choices
• California Phase 3 gasoline regulation approved by California Air Resources
Board in December 1999 prohibits gasoline with MTBE after Dec 31, 2002
• Water quality issues
4

Baharuddin Bin Ali
Renewable Fuel Standard
• Energy Policy Act of 2005
• Replaced oxygenate requirements
• MTBE & ethanol
• Renewable fuel volume mandates
• Ethanol volumes
• 2nd generation production methods
given a higher multiplier to
encourage investment & production
5

Baharuddin Bin Ali
2007 Renewable Fuel Standard
6

Baharuddin Bin Ali
Typical Elemental Analyses:
Petroleum, Biomass, & Biofuels
7

Baharuddin Bin Ali
1st Generation Biofuels
• Ethanol
• Typically derived from fermentation of sugars
& starches
• US: Corn starch
• Brazil: Sugar cane juice
• Biodiesel
• FAME – Fatty Acid Methyl Ester (Malaysia)
• From fats and oils
• US: Soybean oil
• Europe: Rapeseed oil
8

Baharuddin Bin Ali
Edible Constituents of Biomass
• Starch: 70%–75% (corn)
• Readily available and hydrolysable
• Basis for existing U.S. “biorefineries”
• Oil: 4%–7% (corn), 18%–20% (soybeans)
• Readily separable from biomass feedstock
• Basis for oleochemicals and biodiesel
• Protein: 20%–25% (corn), 80% (soybean meal)
• Key component of food
• Chemical product applications
9

Baharuddin Bin Ali
Ethanol From Corn Starch
Two primary processing options
• Wet mills
• Expensive to build – not common
• Sophisticated operations
• Multiple products (Fuel, food, & fiber)
• Dry mills
• Most common – fairly simple operations
• Processing options making more sophisticated
• Limited products – primarily ethanol & Distiller’s Dried
Grains (DDG) with Solubles (DDGS)
• More sophisticated operations may add germ,
fermentation co-products, …
10

Baharuddin Bin Ali
Ethanol from Corn vs. Sugar Cane
11

Baharuddin Bin Ali
Criticisms of Ethanol
• Food vs fuel
– Divert land from growing food to growing fuel
• Just a farmer subsidy
• Ethanol not compatible with gasoline infrastructure
– RBOB – (Reformulated Blendstock for Oxygenate Blending) special blend
stock to allow for RVP increase at E10 levels
– Picks up water
• Cannot be transported in petroleum pipelines – use water slugs between
batches
• Takes more energy to make that you get back
– Based on “wells to wheels” Life Cycle Assessment
– LCA normally compare energy out vs. fossil energy in
– Highly dependent upon feedstock, farming practice, processing, …
• Takes too much water to make
– Highly dependent upon feedstock, farming/irrigation practice, processing,
…
12

Baharuddin Bin Ali
Corn Ethanol Energy Balance
13
Source: M. Wang (2003)

Baharuddin Bin Ali
Biodiesel Cycle
14

Baharuddin Bin Ali
Biodiesel Production
15

Baharuddin Bin Ali
Biodiesel Production Example
16

Baharuddin Bin Ali
2nd Generation Biofuels
• Cellulosic/Lignocellulosic Ethanol
– Biochemical pathway
• Utilize sugars from cellulose & hemicellulose
– Thermochemical pathway
• Utilize all carbon, including lignin
• Butanol
– More closely compatible to petroleum derived gasoline
– From fermentation (BP/DuPont)
– Gasification & catalytic synthesis
• Green/Renewable Diesel/Gasoline
– Hydrocarbon just like petroleum‐derived products
– Multiple sources & processing paths
• Hydro-processed fats & oils
– Both diesel & gasoline
– Could be integrated into existing refineries
• End product from gasification & FT synthesis (Fischer–Tropsch process is a collection
of chemical reactions that converts a mixture of CO and H2 into liquid hydrocarbons.
– Excellent diesel
17

Baharuddin Bin Ali
Non‐Edible Constituents of Biomass
• Lignin: 15%–25%
– Complex aromatic structure
– Very high energy content
– Resists biochemical conversion
• Hemicellulose: 23%–32%
– Xylose is the second most
abundant sugar in the biosphere
– Polymer of 5‐ and 6‐carbon sugars,
marginal biochemical feed
• Cellulose: 38%–50%
– Most abundant form of carbon in
biosphere
– Polymer of glucose, good
biochemical feedstock
18

Baharuddin Bin Ali
Biochemical Conversion Process
19
Lignocellulosic Biomass to Ethanol Process Design and Economics NREL/TP‐510‐32438 June, 2002
http://www.nrel.gov/docs/fy02osti/32438.pdf

Baharuddin Bin Ali
Thermochemical Conversions
• Pyrolysis
• Thermal conversion (destruction) of
organics in the absence of oxygen
• In the biomass community, this
commonly refers to lower temperature
thermal processes producing liquids as
the primary product
• Possibility of chemical and food
byproducts
• Gasification
• Thermal conversion of organic materials
at elevated temperature and reducing
conditions to produce primarily
permanent gases, with char, water, &
condensibles as minor products
• Primary categories are partial oxidation
and indirect heating
20

Baharuddin Bin Ali
Syngas Products
21
• Hydrogen
• Methanol and its
derivatives (NH3, DME,
MTBE formaldehyde,
acetic acid, MTG,
MOGD, TIGAS)
• Fischer Tropsch Liquids
• Ethanol
• Mixed alcohols
• Olefins
• Oxosynthesis
• Isosynthesis
Products from Syngas
TIGAS - Topsoe's Improved Gasoline Synthesis
Process (converts the synthesis gas to
gasoline)
MTG - Methanol-to-Gasoline
MOGD - (Mobil-Olefins-to-Gasoline-and-
Distillate

Baharuddin Bin Ali
Thermochemical Conversion
22
Personal communication Ryan Davis, National Renewable Energy Laboratory. November 2009.

Baharuddin Bin Ali
Hydrodeoxygenation of Organic Oils
• Organic oils can be
hydrotreated to form “green”
diesel
• Fully compatible with
petroleum derived diesel
• Excellent cetane number
because of the straight
chain nature
• Challenges for catalyst design
• Oxygen relatively easy to
remove, but large oxygen
content
• Prefer to deoxygenate to
CO2 to maximize fuel usage
of H2
23
“Hydrotreating in the production of green diesel”, . Egeberg, N. Michaelsen, L. Skyum, & P. Zeuthen
Journal of Petroleum Technology, 2nd Quarter 2010

Baharuddin Bin Ali
Algae
• Better solar collector than land‐based
biomass
• Higher solar utilization
• Lower land use requirements
• Can use brackish water
• Limitation is getting carbon to the
organism
• Co‐locate with power plants –
use CO2 in flue gas
• Biofuels potential
• Kill the algae & harvest its natural oils
• Biodiesel or biocrude feedstock
• Biocatalyst to secrete desired product
• Like yeast for fermentation
• Hydrogen production possible
24
• Near‐term processing steps
• Cultivation
• Open ponds
• Low cost but high potential
for contamination
• Photo bioreactors – flat panel,
tubular, column
• Higher cost but more
controlled conditions
• Harvesting
• High water content of algae
• Oil extraction
• Intercellular rather than
intracellular
• Usually chemical extraction

Baharuddin Bin Ali
Bioethanol Production
25

Baharuddin Bin Ali
Biofuels Production
26

Baharuddin Bin Ali
Biomass Cycle
27

Baharuddin Bin Ali
Composition of Plant Biomass
28
• The chemical composition of plant biomass varies among species. Yet, in
general terms, plants are made of approximately 25% lignin and 75%
carbohydrates or sugars.
• The carbohydrate fraction consists of many sugar molecules linked together
in long chains or polymers.
• Two categories are distinguished: cellulose and hemi-cellulose. The lignin
fraction consists of non-sugar type molecules that act as a glue holding
together the cellulose fibers.
Cellulose Hemi-cellulose Lignin
Softwood 45 25 30
Hardwood 42 38 20
Straw stalks 40 45 15
Typical values for the composition of straw, softwoods and hardwoods

Baharuddin Bin Ali
Where does biomass come from?
The Global carbon cycle
29
• Carbon dioxide (CO2) from the atmosphere and
water absorbed by the plants roots are combined
in the photosynthetic process to produce
carbohydrates (or sugars) that form the biomass.
• The solar energy that drives photosynthesis is
stored in the chemical bonds of the biomass
structural components. During biomass
combustion, oxygen from the atmosphere
combines with the carbon in biomass to produce
CO2 and water.
• The process is therefore cyclic because the carbon
dioxide is then available to produce new biomass.
• This is also the reason why bio-energy is
potentially considered as carbon-neutral, although
some CO2 emissions occur due to the use of fossil
fuels during the production and transport of
biofuels.

Baharuddin Bin Ali
Representation of the Global Carbon Cycle
30
The figure above shows the global carbon reservoirs in Gtons of carbon
(1GtC = 1012 kg) and the annual fluxes and accumulation rates in GtC/year,
calculated over the period 1990 to 1999. The values shown are approximate
and considerable uncertainties exist as to some of the flow values.

Baharuddin Bin Ali
Biomass Resources
31
• Biomass resources can be classified according to the supply sector
Supply
Type
Sector Example
Forestry
Dedicated forestry
Short rotation plantations (e.g. willow, poplar,
eucalyptus)
Forestry by-products Wood blocks, wood chips from thinnings
Agriculture
Dry lignocellulosic energy
crops
Herbaceous crops (e.g. miscanthus, reed canary grass,
giant reed)
Oil, sugar and starch energy
crops
Oil seeds for methyl esters (e.g. rape seed, sunflower)
Sugar crops for ethanol (e.g. sugar cane, sweet sorghum)
Starch crops for ethanol (e.g. maize, wheat)
Agricultural residues Straw, prunings from vineyards and fruit trees
Livestock waste Wet and dry manure
Industry Industrial residues
Industrial waste wood, sawdust from sawmills
Fibrous vegetable waste from paper industries
Waste
Dry lignocellulosic Residues from parks and gardens (e.g. prunings, grass)
Contaminated waste
Demolition wood
Organic fraction of municipal solid waste
Biodegradable land filled waste, landfill gas
Sewage sludge

Baharuddin Bin Ali
Biomass in Malaysia
32
Municipal
Wastes
Sugarcane
1%
Biomass
Rice
1%
Wood
1%
Oil Palm
94%
EFB
Fibre
Shell
POME
Forest
Sawmill
Husk
Straw
Bagasse
Molasses
MSW
Landfill Gas
Organic
Fertlizer
Fronds/
trunk
Abundant in Malaysia > 70 million tonnes collected / year
Production of biomass throughout the year because of –high sunlight intensity/time and high rainfall
Main contributor of biomass is the palm oil industry, mainly ligno-cellulosics
• Malaysia generates in excess of 15,000 tons of solid waste per day
• Malaysian government recognizes the importance of preserving the environment
by promoting recycling (4R)

Baharuddin Bin Ali
Current Applications and Potential of Renewable
Energy (Biomass-Oil Palm Industry)
33

Baharuddin Bin Ali
Current Applications and Potential of
Renewable Energy
(Potential : Biomass-Oil Palm Industry)
34
Industry
Production
(1000 xTon)
Residues
Residues
Product
Ratio
(%)
Residues
Generated
(1000 x
Ton)
Potential
Energy
(PJ)
Potential
Electricity
(MWe)
Oil
palm
59,800
EFB 21.14 12,642 59
570
(at
65%MC)
Fiber 12.72 7,607 113 1080
Shells 5.67 3,391 57 545
Total 23,640 229 2195
Others (POME)
41,860 24 346
Ref: BioGen,2004

Baharuddin Bin Ali
Current Applications and Potential of Renewable Energy
(Biomass : Approved Projects)
35
No.
Type
Energy
Resource
Approved
Application
Grid
Connected
Capacity (MW)
1 Biomass
Empty Fruit
Bunches
15 103.2
Wood
Residues
1 6.6
Rice Husk 1 4.1
Municipal
Solid Waste
4 25
2 Landfill Gas 3 6.0
3 Mini-hydro 23 93.2
Total 47 244
Source: Energy Commission, July 2006

Baharuddin Bin Ali
Applications and Potential of Renewable Energy
(Biomass : Rubber Residues)
36
• The replanting of rubber plantations used to be very important
source of fuel. However, with the development of technology for
the utilization of rubber wood for the manufacture of furniture
and other value-added wood products, the availability of rubber
wood waste for fuel is much decreased.

Baharuddin Bin Ali
(Biomass : Paddy Residues)
37
Industry
Production
Year 2000
(x1000
Ton)
Residues
Residue
product
Ratio
(%)
Residues
Generated
(1000 x
Ton)
Potential
Energy
(PJ)
Potential
Power
( MW )
Rice 2,140
Rice
Husk
22 471 7.536 72.07
Paddy
Straw
40 856 8.769 83.86
TOTAL 2,140 1327 16.305 155.93
Ref:
BioGen,2004

Baharuddin Bin Ali
(Biomass : MSW)
38
Year
Population
(Million)
Estimated
amount
of wastes
(mil.ton/yr)
1991 17.5 4.5
1994 18.9 5.0
2015 31.3 7.8
2020 35.9 9.0
Ref: BioGen,2004
Industrial
24%
Construction
9%
Municipal
2%
Domestic
49%
Commercial/
Institutional
16%
Composition of Solid MSW in Malaysia

Baharuddin Bin Ali
Current Applications and Potential of Renewable Energy
39
• 2 MW installed capacity.
• Fuel by biogas captured from
the landfill area.
• Commissioned in April 2004.
TNB Jana Landfill at
Puchong
TSH Bio Energy
Project
• Located in Kunak, Sabah
• Generation Capacity of 14 MW
(10 MW to be sold to SESB)
• Fuel by oil palm residues (EFB, shells
and fibres)
• Commissioned in December 2004

Baharuddin Bin Ali
Biomass Potential in Malaysia
40
Location
Hectare under oil
palm cultivation
(2005)
Number of Palms
(at 136/Ha)
million
FFB delivered to
Mills
Million Tonnes
Sabah 1,081,102 147 25
Sarawak 405,729 55 6
Peninsula Malaysia 1,956,129 266 43
Total 3,450,960 468 74
Oil Palm planted areas and FFB production in 2005
By 2020 5,500,000 new acreage mainly in Sarawak & Sabah

Baharuddin Bin Ali
Biomass Potential in Malaysia
41
Biomass
Components
Quantity Available
million
tons(2005)
Energy Potential
(MWhr)
Empty fruit bunches
(EFB)
17.0 At 9t/MWh = 1,900
Fibre 9.60
Shell 4.44
Wet shell 1.48 At 2t/MWh = 0.74
Oil Palm Biomass- Energy potential
Sources: MPOB, Malaysian Statistics of Oil Palm 2005

Baharuddin Bin Ali
7th Asian School on Renewable Energy, Puri Pujangga UKM, Malaysia, 16th-20th June 2014 42
Biomass Resource Potential for Malaysia
Renewable Energy Energy Value
(RM mil per annum)
Forest residues 11,984
Oil palm biomass 6,379
Solar thermal 3,023
Mill residues 836
Hydro 506
Solar PV 378
Municipal Waste 190
Rice Husk 77
Landfill gas 4

Baharuddin Bin Ali
Malaysian Gov’t Initiatives in promoting Renewable
Resources
43
Type Energy Resource
Approved
Application
Generation
Capacity (MW)
Grid
Connected
Capacity (MW)
Biomass Empty Fruit Bunches 22 200.5 165.9
Wood Residues 1 6.6 6.6
Rice Husk 2 12.0 12.0
Municipal Solid Waste 1 5.0 5.0
Mix Fuels 3 19.2 19.2
Landfill Gas 5 10.2 10.0
Mini-hydro 26 99.2 97.4
Wind and
Solar
0 0 0.0
Total 60 352.70 316.1
Sources: Hashim, Mazlina, 2005
As of August 2004 , SREP Projects Approved by SCORE stands at 60

Baharuddin Bin Ali
Energy Content in Biomass
44
• The calorific value of a fuel is usually
expressed as Higher Heating Value (HHV)
and/or Lower Heating Value (LHV). The
difference is caused by the heat of
evaporation of the water formed from the
hydrogen in the material and the
moisture. The difference between the two
heating values depends on the chemical
composition of the fuel.
• The HHV correspond to the maximum
potential energy released during complete
oxidation of a unit of fuel. It includes the
thermal energy recaptured by condensing
and cooling all products of combustion.
• The LHV was created in the late 1800s
when it became obvious that
condensation of water vapour or sulfur
oxide in smoke stacks lead to corrosion
and destruction of exhaust systems. As it
was technically impossible to condense
flue gases of sulfur-rich coal, the heat
below 150°C was considered of no
practical use and therefore excluded from
energy considerations.
• The most important property of biomass feedstocks
with regard to combustion – and to the other
thermo-chemical processes - is the moisture
content, which influences the energy content of the
fuel.
• the evolution of the lower heating value (LHV,
in MJ/kg) of wood as a function of the
moisture content.

Baharuddin Bin Ali
Moisture Content For Selected Biomass Resources
45
Biomass resource
Moisture
content
Wt % (wb)
Industrial fresh wood chips
and sawdust
40 – 60
Industrial dry wood chips
and sawdust
10 – 20
Fresh forest wood chips 40 – 60
Chips from wood stored and
air-dried several months
30 – 40
Waste wood 10 – 30
Dry straw 15

Baharuddin Bin Ali
Some typical characteristics of biomass fuels compared to oil and coal
46
• Biomass resources include a wide variety of materials diverse in both physical and chemical
properties. These variations may be critical for the final performance of the system. Some advanced
applications require fairly narrow specifications for moisture, ash content, ash composition. Both the
physical and chemical characteristics vary significantly within and between the different biomass raw
materials.
• However, biomass feedstocks are more uniform for some of their properties compared with
competing feedstocks such as coal or petroleum.
• Coals show gross heating value ranges from 20 - 30 GJ/ton.
• Nearly all kinds of biomass feedstocks destined for combustion fall in the range 15-19 GJ/ton for their
LHV, (most woody materials are 18-19 GJ/tonne), (most agricultural residues are in the region of 15-
17 GJ/ton).
Typical characteristics
GJ/t toe/t kg/m³ GJ/m³
Volume oil
equivalent (m³)Fuel
Fuel oil 41,9 1,00 950 39,8 1,0
Coal 25,0 0,60 1000 25,0 1,6
Pellets 8% moist. 17,5 0,42 650 11,4 3,5
Pile wood (stacked, 50%) 9,5 0,23 600 5,7 7,0
Industrial softwood chips 50% moist. 9,5 0,23 320 3,0 13,1
Industrial softwood chips 20% moist. 15,2 0,36 210 3,2 12,5
Forest softwood chips 30% moist. 13,3 0,32 250 3,3 12,0
Forest hardwood chips 30% moist. 13,3 0,32 320 4,3 9,3
Straw chopped 15% moist. 14,5 0,35 60 0,9 45,9
Straw big bales 15% moist. 14,5 0,35 140 2,0 19,7

Baharuddin Bin Ali
Volume (m³) required to substitute 1 m³ of oil by some other fuels
47

Baharuddin Bin Ali
What is Modern Bioenergy?
48
• Bioenergy is energy of biological and renewable origin,
normally derived from purpose-grown energy crops or by-
products of agriculture.
• Examples of bioenergy resources are wood, straw, bagasse
and organic waste.
• The term bioenergy encompasses the overall technical
means through which biomass is produced, converted and
used.
• Modern bio-energy refers to some technological advances
in biomass conversion combined with significant changes
in energy markets that allow exploring an increased
contribution of biomass to our energy needs, whether
throughout traditional and emerging technological areas
(e.g. from combustion to liquid biofuels).

Baharuddin Bin Ali
The Range Of Costs For Different Fossil And Renewable
Technologies And Fuels
49
• Biomass is the cheapest of the
renewable energies for electricity
production.
• Biomass is present almost
everywhere, indigenous energy
source generation of electricity.
• The figures in blue, represent the
CO2 emissions from each fuel.
• Biomass is a CO2 saver as it emits
only 30 kg of CO2 equiv/MWh (fossil
fuels : range 400 - 800 kg of CO2
equiv/MWh).
• Subsidies are unfairly supporting
high carbon emitters, thus limiting
the growth of renewable
energies. Removal of such subsidies
seems unlikely as this will only
increase electricity prices.
• Gradual reduction in these subsidies
should lead to an increase in low
carbon technology markets.
Subsidies NOT shown

Baharuddin Bin Ali
Bioenergy Key Drivers And Advantages
50
Some bioenergy key drivers consist in its contribution to:
• the reduction of energy dependency on energy imports and
thus, the increased security of supply
• the climate change mitigation (bioenergy use decrease net
greenhouse gas emissions and some other noxious gas
emissions compared to fossil fuels and the fight against
desertification
• stable employment opportunities in rural areas and among
small and medium sized enterprises; this in turn fosters
regional development, achieving greater social and economic
cohesion at community level.

Baharuddin Bin Ali
Other Important Advantages Of Bioenergy
51
• Widespread resources are available
• Biomass resources show a considerable potential in the long
term, if residues are properly valorised and dedicated energy
crops are grown. Bioenergy makes valuable use of some
wastes, avoiding their pollution and cost of disposal
• Biomass has the capacity to penetrate every energy sector:
heating, power and transport.
• Bio-fuels can be stored easily and bioenergy produced when
needed
• Bioenergy creates worldwide business opportunities
• Biofuels are generally bio-degradable and non toxic, which is
important when accident occur.

Baharuddin Bin Ali
Barriers To Bioenergy, Specific Actions Against Them And
Driving Forces To Support These Activities
52
Barriers to bioenergy expansion
• costs of bioenergy technologies and
resources
• competitiveness strongly depends
on the amount of externalities
included in the cost calculations
• resource potentials and
distributions
• lack of organisation in supply
structures for the supply of biofuels
• local land-use and environmental
aspects in the developing countries
• administrative and legislative
bottlenecks.
Overcoming these barriers
• improving the cost-effectiveness of
conversion technologies;
• developing and implementing
modern, integrated bioenergy
systems
• it took farmers thousands of years to
develop plants that are especially
suitable for food. There is therefore a
considerable potential in developing
dedicated energy crops productivity
• establishing bioenergy markets and
developing bioenergy logistics
(transport and delivery bioenergy
resources and products
• valuing of the environmental benefits
for society e.g. on carbon balance.

Baharuddin Bin Ali
Conversion Routes to Bioenergy
53
• The energy available in biomass
may be used either by direct
use as in combustion, or by
initial upgrading into more
valuable and useful fuels such
as charcoal, liquid fuels,
producer gas or biogas.
• Thus, biomass conversion
technologies can be separated
into 4 basic categories:
• direct combustion,
• thermo-chemical
conversion processes
(pyrolysis, gasification),
• bio-chemical processes
(anaerobic digestion,
fermentation) and
• physico-chemical
processes (the route to
biodiesel).

Baharuddin Bin Ali
7th Asian School on Renewable Energy, Puri Pujangga UKM, Malaysia, 16th-20th June 2014 54
Stage Emerging technologies Future technologies
Biomass
resources
• New energy crops
• New oilseed crops
• Bio-waste management
• Bio-engineering of new energy plants
• Development of low-energy agricultural production systems
• Aquatic biomass (algae)
• IT methods in land and biological systems management
Supply
systems
• Use of new agro-machinery
• Biomass densification
• Other simple pretreatments (e.g.
leaching)
• Logistics of supply chains
• Biorefining
• Biotech-based quality monitoring throughout the whole
procurement chain
• IT tools for supply chain modelling and optimal management
Conversion
• Advanced combustion
• Co-combustion
• Gasification
• Pyrolysis
• Bioethanol from sugar and starch
• Bioethanol from lignocellulosics
• Biodiesel from vegetable oils
• Advanced anaerobic digestion
• Biohydrogen (hydrogen from bioconversion of biomass)
• Plasma-based conversions
• Advanced bioconversion schemes
• Other novel conversion pathways (e.g. electrochemical)
• Novel schemes for down-stream processing
(e.g. of pyrolytic liquids or synthetic FT-biofuels)
End
products
• Bioheat
• Bioelectricity
• Transport biofuels
• Upgraded solid biofuels (pellets)
• Use of hydrogen in fuel cells
• Use of FT-biofuels in new motor-concepts e. g. CCS
(Combined Combustion Systems)
• New bio-products (biotech)
• Complex, multi-product systems (IT)
• CO2 sequestration; other new end-use “cultures”
(e.g., user-friendliness, “closed cycle”)
System
integration
• Normalisation and standards
• Best practices
• Economic/ecological modelling
and optimisation
• IT-based management
• Socio-technical and cultural design of applications
• Sustainability based on global as well as local effects

Baharuddin Bin Ali
Biofuels Procurement / Production Costs
55
EU-15 10 NMS + BG + RO
€/GJ €/toe €/GJ €/toe
Tradables
Forestry by-products 2.4 100 2.1 88
Wood fuels 4.3 180 2.7 113
Dry agricultural
residues
3.0 126 2.1 88
Solid industrial residues 1.6 67 2.5 105
Solid energy crops 5.4 226 4.4 184
Imported biofuels 6 251 6 251
Transport fuels
Biodiesel 23 ≈ 960 23 ≈ 960
Bio-ethanol 29 ≈ 1200 29 ≈ 1200
• On average, supply costs of tradable biomass fuels in the EU-15 vary from 1.6 EUR/GJ (solid
industrial residues) to 5.4 EUR/GJ (solid energy crops).
• On average, the supply costs of solid energy crops are close to those of imported biomass, which
was taken at a standard level of 6 EUR/GJ.
• Single average supply costs of 23-29 EUR/GJ were determined for the refined bio-transport fuels
bio-ethanol (from sugar beet and wheat) and biodiesel (from rape and sunflower seed).
Average supply costs of tradable biomass and crops for transport fuels (EUR/GJ).

Baharuddin Bin Ali
Overview of investment costs and production costs of biofuels
56
Investment costs
[€/kWhr]
Productions costs
[€/litre]
Productions costs
[€/GJ]
short
term
Long
term
short
term
long
term
short
term
long
term
Ethanol (sugar crops) 290 170 0.32 - 0.54 15 - 25
Ethanol (wood) 350 180 0.11 - 0.32 5 - 15
RME 150 110 0.50 0.20 15 6
Methanol 700 530 0.14 - 0.20 0.10 9 - 13 7
DME 0.27 14
Fischer-Tropsch diesel 720-770 500-540 0.31 - 0.45 9 - 13
Pyrolysis oil 1.000 790 0.06 - 0.25 4 - 18
HTU diesel 535 400 0.16 - 0.24 5 - 7

Baharuddin Bin Ali
Competitiveness in the electricity market .
Capital costs & efficiencies of principal bioelectricity & competing conversion
technologies
57
Technology
Capital cost in
2002
(EUR/kWe)
Capital cost in
2020
(EUR/kWe)
Electrical
efficiency
(%)
Cost of
electricity in
2020 **
(EUR/MWh)
Existing coal – co-firing 250 250 35 - 40 24 – 47
Existing coal and natural gas
combined cycle – parallel firing
700 600 35 - 40 34 – 59
Grate / fluid bed boiler + steam
turbine*
1500 - 2500 1500 – 2500 20 - 40 57 - 140
Gasification + diesel engine or gas
turbine - (50 kWe – 30 MW)*
1500 - 2500 1000 - 2000 20 – 30 50 - 120
Gasification + combined cycle -
(30 – 100 MWe)
5000 - 6000 1500 - 2500 40 – 50 53 - 100
Wet biomass digestion + engine
or turbine
2000 - 5000 2000 - 5000 25 - 35 52 - 130
Landfill gas + engine or turbine 1000 - 1200 1000 25 - 35 26
Pulverised coal – 500 MWe 1300 1300 35 - 40 48 – 50
Natural gas combined cycle – 500
MWe
500 500 50 - 55 23 - 35
• Larger scale systems will be characterised by the lowest cost and higher efficiency in the value ranges
** 15% discount rate; biomass fuel cost between 7,2 and 14,4 EUR/MWh except for digestion and landfill
gas plants where fuel cost assumed to be zero; coal cost 5,8 EUR/MWh; natural gas cost between 5,4 and
10,8 EUR/MWh. The cost is calculated for electricity supply only and cogeneration could reduce the
electricity cost significantly.
Source: Bauen et. al,2003

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Environmental benefits of Bioenergy
58
+ avoided mining of fossil resources
– emission from biomass production
+ avoided fossil fuel transport (from producer to user)
– emission from biomass fuel transport (from producer to user)
+ avoided fossil fuel utilisation
• One of the key drivers to bioenergy deployment is its positive environmental
benefit, in particular regarding the global balance of green house gas (GHG)
emissions.
• IEA Bioenergy Task 38 (Greenhouse Gas Balances of Biomass and Bioenergy
Systems) investigates all processes involved in the use of bioenergy systems on a
full fuel-cycle basis with the aim of establishing overall GHG balances.
• This is not a trivial matter, because biomass production and use are not entirely
GHG neutral. In general terms, the GHG emission reduction as a result of
employing biomass for energy, read as follows:
Budget breakdown of GHG emission savings

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Environmental Benefits
59
• The real gains are made with that of avoided emissions from the use of fossil
fuels. The balance of the other four matters is not neutral, and in fact slightly
negative for the biomass system. Two GHG emission types are omitted from
the above balance: the negative emission (capture) as a result of biomass
growth, and the positive emission as a result from using the biomass fuel.
They are considered to cancel out.
• GHG emission balances for biomass-fuelled electricity and heat applications
GHG balances for a wide range of technologies to produce electricity and
heat were prepared by Elsayed, Matthews and Mortimer (2003). System
boundaries encompassed the entire chain from fuel production to end-use.
• Some biomass systems show net GHG emissions savings of more than 40%
of the substituted fossil alternatives, while some others only score 4%.
• Thus, the span of the environmental benefit is wide, and the effective value
will depend on the particular application situation (technology, scale etc).
• The total GHG emissions from contaminated biomass fuels (non-tradables)
are set at 0, since these fuels are available anyway. There existence cannot
be avoided, and all GHG emissions associated with their production should
be allocated to the products from which they are the unavoidable result.

Baharuddin Bin Ali
GHG savings for selected technologies to produce electricity and heat
from biomass fuels
60
Source: Elsayed, Matthews and Mortimer (2003).

Baharuddin Bin Ali
GHG Emission Balances Of Selected Bio-transport Fuels
61
• For an assessment of GHG emission reduction that result from replacing
fossil transport fuels by biofuels, the entire life cycle of the respective
fuels is usually considered from well to wheel. A complete life cycle
analysis (LCA) of emissions takes into account
• the direct emissions from vehicles and also those associated with the
fuel’s production process, (extraction, production, transport,
processing and distribution).
• Ranges in data result from local variations between fuel routes and
differences in technology, which may occur at all stages of the well-
to-wheel fuel chain.
• The pivots indicate the uncertainty related to the used data.
• The substitution of biodiesel for petrol results in a total GHG emission
reduction of 45-80%. If replacing fossil diesel fuel, this emission reduction
is smaller, because diesel shows lower CO2-equivalent well-to-wheel
emissions than petrol. The range of ethanol-starch is quite broad, which
can be partly explained by differences in crop (corn, sugar beet,
molasses), and differences in technology.

Baharuddin Bin Ali
GHG Savings For Selected Bio-transport Fuels
62
Source: Elsayed, Matthews and Mortimer (2003)

Baharuddin Bin Ali
Global GHG Emission Savings
63
• From the White Paper issued in 1997, it appears that biomass would be the
biggest contributor in absolute terms to the CO2 emissions reduction effort.
Estimated CO2 benefits from the increase of renewable energy in the EU
primary energy supply
Additional capacity
(1997-2010)
CO2 reduction
(Mt CO2-eq./year)
Biomass 90 Mtoe 255
Wind 36 GW 72
Hydro 13 GW 48
Solar collectors 94 Mio m2 19
Geothermal 2.5 GW 5
Photovoltaic 3 GWp 3

Baharuddin Bin Ali
Employment Benefits
64
• Bioenergy is a decentralised energy option whose implementation presents positive impacts on
rural development by creating business and employment opportunities. Jobs are created all
along the bioenergy chain, from biomass production or procurement, to its transport,
conversion, distribution and marketing.
• Bioenergy appears as the most labour-intensive sector among renewables. The jobs created
range from manual ones to specialised engineering and administration positions.
• Through liquid biofuels, bioenergy can also offer agriculture an opportunity to diversify its
market outcomes.
• From the perspective of bioenergy projects, the term employment usually includes three
different categories. Direct employment results from operation, construction and production.
In the case of bioenergy systems, this refers to the total labour necessary for crop production,
construction, operation and maintenance of conversion plants, and for the transportation of
biomass.
• Indirect employment is jobs generated within the economy as a result of expenditures related
to biomass fuel cycles. Indirect employment results from all activities connected, but not
directly related, such as supporting industries, services and similar.
• The higher purchasing power, due to increased earnings from direct and indirect jobs may also
create opportunities for new secondary jobs, which may attract people to stay or even to move
in. These latter effects are referred to as induced employment.
• The main issue is whether the bioenergy project will provide earnings that are high enough for
long enough to make it worthwhile to mobilise local resources for implementation.

Baharuddin Bin Ali
An estimate of the employment effect of forest chips production in
Finland by 2010
65
Product
Production
1000 m3
Man.years/
1000 m3
Man.years/
annum
Small tree chips
- whole tree chips, mechanised cutting 600 0.60 360
- whole tree chips, manual cutting 200 1.20 240
- stemwood chips, self-employed forest
owners
200 2.00 400
Logging residues chips 2500 0.30 750
Stump chips 1500 0.35 525
Forest chips, total 5000 0.45 2275

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Employment per PJ Annual Fuel Consumption Among Selected
European Projects
66
Biomass source/
technology
MWth
Direct
jobs
Indirect
jobs
Induced
jobs
Total
jobs
Multiplier Country
SRC, gasifier 2 51 11 36 98 1.25 The UK
Miscanthus, heat 0.13 321 0 214 534 1.21 Belgium
Forest residues, CHP 40 52 33 30 115 1.30 France
Triticale, proc. Heat 2 134 60 28 222 1.33 Germany
Artichoke, heat 1 269 19 93 380 1.50 Greece
SRC, gasifier 5 36 21 23 80 1.29 Ireland
Ind. Residues, CHP 17 41 11 13 65 1.46 Italy
Waste etc. CHP 5 13 2 27 42 1.18 Netherlands
Logging Residues,
heat
10 52 2 21 76 1.26 Sweden

Baharuddin Bin Ali
Impact Of Renewable Technologies On Employment In The
European Union
67
Technology 2005 2010 2020
Bioenergy 449,928 642,683 838,780
- Energy crops and residues,
forest residues
307,641 416,538 515,364
- Bio-anaerobic 37,223 70,168 120,285
- Bio-thermal 94,164 123,608 154,422
- Liquid biofuels 10,900 32,369 48,709
Solar thermal heat 4590 7390 14, 311
PV 479 -1769 10,231
Solar thermal electric 593 649 621
Wind onshore 8690 20,822 35,211
Wind offshore 530 -7968 -6584
Small hydro -11,391 -995 7977
TOTAL 453,418 660,812 900,546
Source: IEA, 2003 (from the ECOTEC study “The impact of renewables on employment and
economic growth. Directorate General for Energy, European Commission, 1999.)
• The use of renewable energy technologies will more than double by 2020 and will lead to the
creation of about 900,000 jobs by 2020.
• More than 90% of these jobs (approximately 840,000) will be in the bioenergy sector and
500,000 of them in the agricultural industry in order to provide primary biomass fuels.
Impact of renewable technologies on employment in the European Union
(new net jobs FTE employment relative to base in 1995)

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Bioenergy employment in the EU
68
Bioenergy employment in the EU (new net jobs FTE employment
relative to base in 1995

Baharuddin Bin Ali
Bioenergy employment in the EU
69
• There is quite a wide consensus that, over the coming decades, modern biofuels will
provide a substantial source of alternative energy. Nowadays, biomass already provides
approximately 11-14% of the world’s primary energy consumption (data vary according
sources). There are significant differences between industrialised and developing
countries, as shown in the figure below. In particular, in many developing countries
bioenergy is the main energy source.
Bioenergy contribution worldwide as a fraction of total energy consumption

Baharuddin Bin Ali
Biomass in Relatively Poor Countries
70
• For 75% of the world’s population living in developing countries, biomass is the most
important source of energy.
• With increases in population and per capita demand, and depletion of fossil-fuel resources,
the demand for biomass is expected to increase rapidly in developing countries.
• On average, biomass produces 35 % of the primary energy in developing countries, but many
sub-Saharan countries depend on biomass for up to 90 %.
• Biomass will remain an important global energy source in developing countries well into the
next century.
• Despite its wide use in developing countries, biomass is used with very low efficiency
applications.
• The overall efficiency in traditional use (e.g. cooking stoves) is only about 5 - 15 %, and
biomass is often less convenient to use compared with fossil fuels.
• It can also be a health hazard in some circumstances. For example, cooking stoves can release
particulates, carbon monoxide (CO), nitrous oxides (NOx) and other organic compounds in
poorly ventilated homes, often far exceeding the recommended World Health Organisation
levels.
• Furthermore, inefficient biomass utilisation is often associated with the increasing scarcity of
hand-gathered wood, nutrient depletion, and the problems of deforestation and
desertification.

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Bio-energy in the EU
71
Bio-energy in the EU
• In the EU, renewable energy sources provide approximately 6% of
the total gross inland energy consumption (5.7% in 2002 for the
EU-25).
EU-25 gross inland consumption by fuel

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Contribution of RES to the EU Primary Energy Supply
72
EU-15 EU-25
Mtoe % Mtoe %
Renewables 85,3 100% 94,9 100%
Biomass 53,9 63% 62,1 65%
Hydro 24,2 28% 25,6 27%
Wind 3,1 4% 3,1 3%
Solar 0,5 1% 0,5 1%
Geothermal 3,7 4% 3,7 4%
• Bioenergy contributes about 64% of all RES primary energy
requirements of the European Union, about 98% of RES heat and 9%
of RES electricity. Bioenergy use in EU countries varies from 1% in the
UK to 20% in Finland.
Contribution of RES to the EU primary energy supply (2002)
Source: EUROSTAT

Baharuddin Bin Ali
Contribution of RES to the EU Primary Energy Supply
73

Baharuddin Bin Ali
Biomass Resources Assessments
74
Biomass resources assessments
• Biomass resources and potential are considerable. Estimations vary
according to the calculation methodology and the assumptions made
(e.g. land use patterns for food production, agricultural management
systems, wood demand evolution, production technologies used,
natural forest growth etc). It is also common to distinguish several
potentials:
• Theoretical potential: the theoretical maximum potential is
limited by factors such as the physical or biological barriers that
cannot be altered given the current state of science.
• Technical potential: the potential that is limited by the technology
used and the natural circumstances.
• Economic potential: the technical potential that can be produced
at economically profitable levels.
• Ecological potential: the potential that takes into account
ecological criteria, e.g. loss of biodiversity or soil erosion.

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Biomass resources : World Bioenergy Potential
75
• Bioenergy could in principle provide all the world’s energy
requirements, but its real technical and economic potential is much
lower 10%.
• The WEC Survey of Energy Resources (2001) estimates that bioenergy
could theoretically provide 2900 EJ/y, but that technical and economic
factors limit its current practical potential to just 270 EJ/y.
• Table B1 shows the potential and current use of bioenergy by region.
Even with the current resource base, the practical potential of
bioenergy is much greater than its current exploitation.
• Obstacles to greater use of bioenergy include poor matching between
demand and resources, and high costs compared to other energy
sources.
• Projections by the WEC, WEA and IPCC estimate that by 2050
bioenergy could supply a maximum of 250–450 EJ/y, representing
around 25% of global final energy demand.
• The technological potential of bioenergy at 30% of global energy
demand.

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Current Technical Potentials And Biomass Use Compared To Primary
Energy Consumption (PEC) From Fossil Fuels & Hydro
76
PEC fossil
fuels +
hydro
Bioenergy
use
Bioenergy
potential
Use /
potential
Use /
PEC
Potential /
PEC
(EJ/year) %
North-America 104.3 3.1 19.9 16% 3% 19%
Latin-America & Caribbean 15.1 2.6 21.5 12% 17% 142%
Asia * 96.8 23.2 21.4 108% 24% 22%
Africa 11 8.3 21.4 39% 75% 195%
Europe 74.8 2 8.9 22% 3% 12%
Former USSR 37.5 0.5 10 5% 1% 27%
Total 339.5 39.7 103.1 39% 12% 30%
Current technical potentials and biomass use compared to primary energy
consumption (PEC) from fossil fuels & hydro
• In Asia the actual use of biomass is higher than the potential. The value for potential and actual use
refer to sustainable use, indicating that in the case of Asia the actual use is not sustainable, i.e. it
can not be sustained over a long period, due to e.g. limited land availability
Source: Kaltschmitt, 2001

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Current Technical Potentials And Biomass Use Compared To Primary
Energy Consumption (PEC) From Fossil Fuels & Hydro
77

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Estimation of Global Conventional And Biomass Resources
78
Energy category Million toe EJ
Oil statistics (ENI, 2003-2004)
Annual oil extraction 3850 161.2
World oil reserves 149600 6263.5
World energy statistics (IEA, 2003)
World annual primary energy supply 10376 434.4
- Oil 3715 155.5
- Coal 2379 99.6
- Natural gas 2169 90.8
- Renewables & Waste 1121 46.9
- Nuclear 695 29.1
- Hydro 228 9.5
- Other (includes geothermal, solar, wind, etc.) 52 2.2
EUROSTAT, EU-25 Energy statistics (2002)
Annual gross inland consumption (GIC) 1680 70.3
Share of renewable energy sources in GIC 95 4.0
Share of bioenergy in GIC 62 2.6
EU-25 (+Bulgaria, +Romania) biomass available potential (BTG, 2004)
Biomass available potential by 2010 183 7.7
Biomass available potential by 2020 210 8.8

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Estimation of Global Conventional And Biomass Resources
79
Energy category Million toe EJ
EUBIA
2020 biomass potential in the EU-25 200 8.4
2050 biomass potential in the EU-25 400 16.7
EU-25 forest biomass, crop residues and energy crops (Ericsson, Nilsson, 2004)
Scenario 1 (short term, 10-20 years) 105 4.4
Scenario 2a (medium term, 20-40 years; low harvest) 184 7.7
Scenario 2b(medium term, 20-40 years; high harvest) 220 9.2
Scenario 3a (long term, >40 years; low harvest) 375 15.7
Scenario 3b (long term, >40 years; high harvest) 451 18.9
World bioenergy potential from forestry by 2050 (Smeets et al., 2004)
Low demand 764 32.0
Medium demand 1027 43.0
High demand 1242 52.0
Bioenergy technical production potentials from agricultural residues and
bioenergy production on surplus agricultural lands to 2050 (Smeets et al., 2004)
World min. 6520 273.0
World max. 35134 1471.0
West Europe min. 191 8.0
West Europe max. 597 25.0
East Europe min. 96 4.0
East Europe max. 693 29.0

Baharuddin Bin Ali
Availability of bioenergy in Europe in 2000, 2010 and 2020 (Mtoe/yr)
80
Source: BTG, 2004
EU-15 10 NMS + BG, RO
2000 2010 2020 2000 2010 2020
Tradables: 86 93 101 21 22 24
Forestry by products & (refined) wood fuels 34 38 42 7.9 8.7 9.6
Solid agricultural residues 25 28 31 7.3 8.1 8.9
Solid industrial residues 11 12 13 2.1 2.4 2.6
Solid energy crops* 16 16 16 3.2 3.2 3.2
Non-tradeables: 40 53 66 7.1 9.4 13
Wet manure 11 12 13 3.4 3.8 4.2
Organic waste
- Biodegradable municipal waste 6.7 17 28 0.5 2.5 5.7
- Demolition wood 5.3 5.8 6.4 0.6 0.6 0.7
- Dry manure 1.9 2 2.3 0.4 0.4 0.5
- Black liquor 9.9 11 12 0.7 0.8 0.9
Sewage gas 1.7 1.9 2.1 0.4 0.4 0.5
Landfill gas 4.0 3.8 2.1 1.1 0.9 0.4
Transport fuels 4.9 4.9 4.9 0.8 0.8 0.8
Bio-ethanol* 3.7 3.7 3.7 0.5 0.5 0.5
Bio-diesel* 1.2 1.2 1.2 0.3 0.3 0.3
Total bio-energy 131 151 172 28 32 38
*: It is assumed that 50% of the set-aside area is available for solid energy crops and 25% each for liquid bio-
fuel (bio-ethanol and biodiesel) crops
Note the growth in the availability of organic wastes, which results from the EU implementation of the EC
directive on the landfill of waste (1999/31/EC). This directive discourages the land filling of biodegradable
waste and prescribes a time schedule to reduce this waste disposal to a specific level.

Baharuddin Bin Ali
Trade of Biofuels
81
• The most critical non-technical barrier to bioenergy is the availability of resources to ensure long-term
supply at a reasonable cost. International trade of solid biomass fuels and this supply chain is an important
element in the development of bioenergy on a global scale.
• Biofuels are usually produced and used locally. This pattern has changed in northern Europe due to industrial
and large scale uses (e.g. in district heating systems) of different forms of biofuels.
• Today, solid biofuels like wood residues, pellets and wood chips are traded in Europe and have reached 50
PJ/a. International biomass trade can provide biofuels at lower prices. The largest volumes of biomass are
traded from the Baltic countries (Estonia, Latvia, Lithuania) to the Nordic countries (especially Sweden,
Denmark, Finland). Some are also traded from Finland to other Nordic countries, and between neighbouring
countries in Central Europe, especially the Netherlands, Germany, Austria, Slovenia and Italy. The traded
biofuel is most often of refined wood fuels (pellets and briquettes) and industrial by-products (sawdust,
chips), in Central Europe also wood waste.
• Bio-ethanol has also become a global commodity. Since May 2004, futures in bioethanol are traded at the
New York stock exchange.
• Land availability for fuel crops in Europe is limited. From the current 6 million ha of set aside in the EU-15,
approximately 7 Mtoe of RME could be produced, or 8.5 – 16 Mtoe of bio-ethanol (respectively from wheat
or sugar beet). This corresponds to 2.1 – 4.7% of the fuel used for transport (338 Mtoe in 2002).
• Brasil could have a production potential in the region of 100 Mtoe/year by 2020. Therefore, biofuels use in
the EU is likely to be supported by global trade. Tropical countries are the most interesting stakeholders in
biofuels due to their favourable production conditions. Moreover, their experience (e.g. Brasil) can be
instrumental for biofuel development in the European context.

Baharuddin Bin Ali
Research & Development
in Biofuels and Bioenergy
82

Baharuddin Bin Ali
R & D Orentations
83
• In order to foster the development of sustainable biomass-based energy
technologies, different fields of research must be integrated.

Baharuddin Bin Ali
R&D and Policy Needs for Achieving Vision Goals
84

Baharuddin Bin Ali
Crosscutting Impacts of Feedstock Production R&D
85

Baharuddin Bin Ali
R&D : Plant Biochemistry & Enzymes
86

Baharuddin Bin Ali
R&D : Chemical & Biological Pathways
87

Baharuddin Bin Ali
R&D : Agronomic Pathways
88

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R&D : Feedstock Logistics & Handling Pathways
89

Baharuddin Bin Ali
Crosscutting Benefits of Processing & Conversion
90

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R&D : Thermochemical Conversion
91

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R&D : Bioconversion
92

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R&D : Biorefinery
93

Baharuddin Bin Ali
R&D : End-Products & Distribution System
94

Baharuddin Bin Ali
Quranic Inspiration
95
"The same Who produces for you fire out of the
green trees, when behold! Ye kindle therewith
(your own fires)!
(Surah Yaasin : 80)

Baharuddin Bin Ali
Operational problems in biomass combustion
96
• Complete combustion produces minimum pollution and depends on the
combustion chamber temperature, the turbulence of the burning gases,
residence time and the excess O2 These parameters are governed by :
• combustion technology (e.g. combustion chamber design, process control)
• settings of the combustion (e.g. primary and secondary air ratio,
distribution of the air nozzles)
• load condition (full- or part-load)
• fuel characteristics (shape, size distribution, moisture content, ash content,
ash melting behaviour).
• Biomass is difficult to handle and combust due to low energy density and
presence of inorganic constituents.
• Some types of biomass contain significant amounts of chlorine, sulfur and
potassium. The salts, KCl and K2SO4, are quite volatile, and the release of these
components may lead to heavy deposition on heat transfer surfaces, resulting
in reduced heat transfer and enhanced corrosion rates. Severe deposits may
interfere with operation and cause unscheduled shut downs.
• The release of alkali metals, chlorine and sulfur to the gas-phase may also lead
to generation of significant amounts of aerosols (sub-micron particles) along
with relatively high emissions of HCl and SO2.

Baharuddin Bin Ali
Operational problems in biomass combustion
97
• The nature and severity of the operational problems related to biomass depend on the choice of
combustion technique.
• In grate-fired units deposition and corrosion problems are the major concern.
• In fluidized bed combustion the alkali metals in the biomass may facilitate agglomeration of
the bed material, causing serious problems for using this technology for herbaceous based
biofuels. Fluidized bed combustors are frequently used for biomass (e.g. wood and waste
material), circulating FBC are the preferred choice in larger units.
• Application of biomass in existing boilers with suspension- firing is considered an attractive
alternative to burning biomass in grate-fired boilers.
• However, also for this technology the considerable chlorine and potassium content in some
types of biomass (e.g. straw) may cause problems due to deposit formation, corrosion, and
deactivation of catalysts for NO removal (SCR).
• Currently wood based bio-fuels are the only biomasses that can be co-fired with natural gas; the
problems of deposition and corrosion prevent the use of herbaceous biomass. However, significant
efforts are aimed at co-firing of herbaceous biomass together with coal on existing pulverized coal
burners.
• For some problematic fuels, esp. straw a separate auxiliary boiler may be required. In addition to
the concerns about to deposit formation, corrosion, and SCR catalyst deactivation, the addition of
biomass in these coal units may impede the utilization of fly ash for cement production. In order to
minimize these problems, various fuel pretreatment processes have been considered, including
washing the straw with hot water or using a combination of pyrolysis and char treatment.

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Cogeneration
98
• Cogeneration is the combined production
of electrical (or mechanical) and useful
thermal energy from the same primary
energy source.
• It encompasses a range of technologies,
but always includes an electricity
generator and a heat recovery system.
Cogeneration is also known as combined
heat and power (CHP).
• Comparison:
• Conventional power generation, on
average, is only 35% efficient – up to
65% of the energy potential is released
as waste heat.
• Combined cycle generation can improve
efficiency to 55%, excluding losses for
the transmission and distribution of
electricity.
• Through the utilisation of the heat, the
efficiency of cogeneration plant can
reach 90% or more.

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Benefits of Co-generation
99
• Cogeneration installations are usually sited as near as possible to the
place where the heat is consumed and, ideally, are built to a size to
meet the heat demand. Otherwise an additional boiler will be
necessary, and the environmental advantages will be partly hindered.
This is the central and most fundamental principle cogeneration.
• The benefits of cogeneration are:
• Increased efficiency of energy conversion and use, and thus large
cost savings, providing additional competitiveness for industrial
and commercial users, and offering affordable heat for domestic
users
• Lower emissions to the environment, in particular of CO2
• An opportunity to move towards more decentralised forms of
electricity generation, and to improve local and general security
of supply

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Deployment of Cogeneration
100
• Cogeneration is an established technology. Its ability to provide a
reliable and cost-effective supply of energy has been proven.
Cogeneration is currently used on many thousands of sites
throughout the EU, and supplied around 10% of both the electricity
generated and heat demand in the EU-15 in 1999. The EU target is to
reach 18% by 2010. The following table illustrates what this target
could achieve in terms of CO2 emissions reduction. The results are
different depending on the fuel being displaced:
Fuel displaced
CO2
savings
Million
tonnes
Coal electricity and coal boilers 342
Gas electricity and gas boilers 50
Fossil mix and boilers 188
Source: COGEN

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Applications of Cogeneration
101
• There are 4 broad categories of cogeneration applications:
1. small-scale cogeneration schemes, usually designed to meet space and
water heating requirements in buildings, based on spark ignition
reciprocating engines
2. large-scale cogeneration schemes, usually associated with steam raising in
industrial and large buildings applications, and based on compression
ignition reciprocating engines, steam turbines or gas turbines
3. large scale cogeneration schemes for district heating based around a power
station or waste incinerator with heat recovery supplying a local heating
network
4. Cogeneration schemes fuelled by renewable energy sources, which may be
at any scale.
• Since 1990, significant technological progress has been made to enable engine
and turbine technology to be widely implemented and promote more
decentralised forms of cogeneration and power generation. Cost-effectiveness
and decreasing emissions have resulted. There are an increasing number of
varied applications in industry and residential areas and which can be used in
heating and cooling applications.

Baharuddin Bin Ali
Cogeneration Technologies
102
• A cogeneration plant consists of 4 basic elements:
1. a prime mover (engine),
2. an electricity generator,
3. a heat recovery system and
4. a control system.
• Cogeneration units are generally classified by the type of prime mover
(i.e. drive system), generator and fuel used. Currently available drive
systems for cogeneration units include:
• Reciprocating engines
• Steam turbines
• Gas turbines
• Combined cycle
• New developments are bringing new technologies towards the market. It
is expected that fuel cells, Stirling engine and micro-turbines will become
economically available from in the next decade.

Baharuddin Bin Ali
Typical Cogeneration Systems
103
Prime mover Fuel used
Size range
(MWe)
Heat: power
rat
Electrical
efficiency
Overall
efficiency
Heat quality
Pass out steam
turbine
Any fuel 1 - 100+ 3:1 - 8:1+ 10 - 20% Up to 80%
Steam at 2
Press or more
Back pressure
steam turbine
Any fuel 0.5 – 500 3:1 - 10:1+ 7 - 20% Up to 80%
Steam at 2
Press or more
Combined
cycle gas
turbine
Gas, biogas, gasoil,
LFO,
LPG, naphtha
3 - 300+ 1:1 - 3:1* 35 – 55% 73 - 90%
Medium grade
steam; high temp.
hot water
Open cycle
gas turbine
HFO,
LFO, LPG, naphtha
0.25 - 50+ 1.5:1 - 5:1* 25 – 42% 65 – 87%
High grade steam;
high temp. hot
water
Compression
Ignition engine
HFO,
LFO, naphtha
0.2 - 20 0.5:1 - 3:1* 35 – 45% 65 - 90%
Low pressure
steam low;
medium temp.
hot water
Spark
ignition engine
Gas, biogas, LHO,
naphtha
0.003 – 6 1:1 - 3:1 25 - 43% 70 - 92%
Low and medium
temp. hot water
* Highest heat:power ratios for these systems are achieved with supplementary firing.
Source: COGEN

Baharuddin Bin Ali
Gasification
104
The SilvaGas® Gasification Process
• The SilvaGas gasification technology underwent
initial development at Battelle’s Columbus
Laboratories as a part of the USA DOE’s Biomass
Power Program.
• In the process, biomass is indirectly heated using a
hot sand stream to produce a medium calorific
value gas (approximately 17 to 19 /Nm3.

Baharuddin Bin Ali
The SilvaGas® Gasification Process
105
• The process uses 2 circulating fluidized bed reactors as the
primary process vessels. The circulating sand is used as a
heat transfer medium to rapidly heat the incoming
biomass and convey char from the gasification reactor into
the process combustor.
• Thermal gasification of biomass provides flexibility for the
production of the complete slate of products in a virtual
“biomass refinery". Indirect gasification holds great
potential as a means for generating a flexible product gas
capable of fulfilling a range of energy needs by its direct
use or as input to a synthesis reactor. By providing a full
scale demonstration of the SilvaGas process, the VGP has
been used to validate the technology and confirm its
commercial viability.
• The flexibility of the medium Btu gas produced in the
SilvaGas process allows its use for:
• Direct use as a fuel gas that can be interchanged with
natural gas or distillate oil
• Co-fired with biomass or fossil fuels for heating or
power applications,
• Use as a fuel for advanced power generation cycles
including turbines or fuel cells, and
• Use as a feed gas for synthesis applications such as
production of Fisher Tropsch liquids, alcohols, and
hydrogen.

Baharuddin Bin Ali
A Commercial Scale Demonstration Plant
106
• Designed for 182 dry tonnes (200 tons) per day of biomass feed. based on the SilvaGas
process was constructed in Burlington, Vermont. Burlington Electric Department’s (BED)
McNeil station and commissioned in 1999.
• BED’s McNeil station, 50 MW, is one of the world’s largest wood fired power stations.
• It uses conventional biomass combustion technology, a stoker grate, conventional steam
power cycle, and particulate removal using ESP’s.
• BED improves its generating efficiency by implementing a gasification combined cycle system.
• The gas produced is being used as a co-fired fuel in the existing McNeil power boilers.
• A gas combustion turbine is installed to accept the product gas from the gasifier
• The SilvaGas process uses short residence time circulating fluidized bed reactors for both the
gasification and combustion systems.
• Gasifier capital costs for a 400 ton per day (dry biomass basis) gasification plant have been
estimated to be approximately USD12.0 million.
• This facility will produce > 200 million Btu/hr of medium Btu product gas plus recoverable
sensible energy from the flue gas and product gas streams of approximately 46 million
Btu/hr.
• If a net zero cost biomass fuel is assumed, a 12% ROI can be realized with a medium Btu gas
selling price of $3.00/MM Btu – a value competitive in today’s energy market.
• These favorable economics reflect the simplicity of operation of the SilvaGas system. Only
one operator is required for plant operations, exclusive of feedstock handling.
• This gas selling price does not reflect any potential tax credits or “green energy” credits.

Baharuddin Bin Ali
The Vermont Gasification Project
107
Indirect
Gasifier
Biomass
Biogas
Heat Recovery Flue Gas
Steam turbine
Generator
Electricity
Char
Combustor
Hot
Sand
Steam Air
Gas turbine
Fuel Gas
Comp
Steam
Char
&
Sand
Scrubber
To heat
recovery
& exhaust
Dryer
Boiler

Baharuddin Bin Ali
Vermont Gasifier General Layout View From West Vermont Gasifier General Layout View From East
108

Baharuddin Bin Ali
The Vermont Gasification Project
109
The Vermont Gasification Plant (the largest in the world)

Baharuddin Bin Ali
The Battelle High Throughput Gasification Process
110

Baharuddin Bin Ali
Pyrolysis Of Biomass
111
• Pyrolysis is a very old energy technology
• Vehicles were run on gas produced by pyrolysis of wood in
times of war.
• Main advantages over conventional combustion
technologies:
• The combined heat and power generation via biomass
gasification connected to gas-fired engines or gas turbines
can achieve significantly higher electrical efficiencies (22 -
37 %)
• Using the produced gas in fuel cells for power generation
can achieve an even higher overall electrical efficiency of
25 - 50 %, even during partial load operation
• Improved electrical efficiency of the energy conversion via
pyrolysis means greater reduction in CO2.
• Reduced NOx compounds and removal of pollutants in
most cases. The NOx advantages may be partly lost if the
gas is consumed in gas-fired engines or gas turbines.
• Significantly lower emissions of NOx, CO and hydrocarbons
when the gas is used in fuel cells.
Steam is used to gasify
biomass in order to get
higher quality gas

Baharuddin Bin Ali
112
• Pyrolysis of biomass generates 3 different
energy products in different quantities:
coke, gas and bio-oils.
• Flash pyrolysis gives high bio-oil yields,
but requires further technical R&D efforts
to process bio-oils
• Pyrolysis as the first stage in a 2-stage
gasification plant for straw and other
agricultural materials does deserve
consideration.
• In the typical biomass gasification
process, air is used as the gasifying agent
and hence the gas has a low calorific
value (3-5 MJ/m3). After cleaning it can
be used in gas-fired engines or gas
turbines.
Flash pyrolysis of biomass in action

Baharuddin Bin Ali
113
• Gas turbines connected to a steam turbine will burn medium calorific value
(MCV) gas (12-15 MJ/m³) more favourably than low calorific gas. The use of
steam injection into the gas turbine combustion chamber (Cheng process)
requires at the very least MCV gas.
• The production of hydrogen or methanol from gasification of biomass or the
use of producer gas in low-temperature fuel cells also require either gasifiers
that operate with highly-enriched oxygen and steam, or indirectly heated
gasifiers must be used with steam as a gasification medium to generate the
necessary medium calorific value producer gas with high hydrogen content.
• Gasification of wood, wood-type residues and waste in fixed bed or fluidised
bed gasifiers with combustion of the gas for heat production is now standard.
• Much greater technical problems are posed by gasification of straw and other
solid agricultural materials, which generally have much higher concentrations
of chlorine, nitrogen, sulphur, and alkalis.
• The gasification of green biomass is still at an early stage of development.
Strengthened development efforts on gasification technologies for green
biomass materials are essential as the potential supply of this type of fuels is
comparatively large.

Baharuddin Bin Ali
114
• Efficient cleaning of the gas and correct
adaptation of the products of biomass
gasification to the specific requirements of the
gas combustion systems are prerequisites for
use in gas-fired engines, gas turbines and fuel
cells.
• Tar compounds can be effectively removed by
increasing the gas temperature or by catalytic
cracking over nickel. There is still no
economically viable solution of this problem.
Tar is one of products of
gasification of biomass
• None of the gasifier types currently available have been successfully tested in
connection with gas-fired engines in long term operation in working
combined heat and power stations
• Pressurised gasification achieves higher overall electrical efficiencies, but
requires greater technical resources to feed the biomass into the gasifier, and
problems with gas cleaning may occur. The gas produced consists mainly of
high levels of carbon monoxide and hydrogen, coupled with some methane
and other combustibles.

Baharuddin Bin Ali
115
• For power plants with integrated biomass gasification in the range 3 - 20
MW electricity, fluidised bed gasification of biomass under atmospheric
pressure, coupled with gas turbines using the Cheng cycle or gas and
steam turbines appear to be the most promising technology at present in
technical and economic terms.
• For combined heat and power stations with capacities up to about 2 MW
electricity, gas use in gas-fired engines is, at the moment, more attractive
than gas turbines.
• Because of problems with fuel supply and transport, biomass gasification
plants with capacities above 30 MW electricity are not a viable
proposition in most countries.
• The co-firing of biomass in existing large coal power stations (< 100 MW)
is currently being investigated in various countries. The integration of
biomass-fuelled gasifiers in coal-fired power stations would have certain
advantages over stand-alone biomass gasification plants. Most important
are the improved flexibility in response to annual and seasonal fluctuations
in biomass availability and the lower investment costs.

Baharuddin Bin Ali
116
• Organic (carbon-based) compounds and materials can be "broken down" into
their constituent elements when rapidly exposed to high temperatures in the
absence of oxygen; this process is called "fast pyrolysis“. The process produces
gases, liquids and solids (char).
• The exact composition and volume of products produced varies depending on
the specific biomass being processed:
• combustible gases and BIO-oil can be used as a renewable, clean burning
source of energy for heating, motive power and electrical generation.
• Non combustible gases (primarily CO2) could be utilized in green house
operations.
• BIO-oil can be further processed into chemical feed stock for industrial and
commercial applications
• Carbon char can be utilized as a fuel source, or sold as a carbon compound
• Ash can be utilized as an additive for cement production or agricultural
fertilizer
• The high temperature nature of pyrolysis will destroy pathogens and can also
act to isolate and concentrate chemical pollutants for appropriate disposal.

Baharuddin Bin Ali
117

Baharuddin Bin Ali
Pyrolysis Benefits
118
• Production of valuable liquid, gaseous and solid products from
agricultural wastes
• Renewable "green" energy source (bio-oil) for use in motive
power, electrical generation and/or heating
• Reduction of prohibitive feed stock shipping costs
• Reduction of pollution from agricultural waste, particularly the
burning of certain straws (rice & flax)
• Destruction of pathogens in potentially hazardous materials
(animal renderings)
• Soil nutrient recovery N, P, C additives in char and ash used as
fertilizer additives
• Adaptable to many different agricultural and agri-food
materials, solid, or liquid
• Bench test lab facilities available for pre-testing new materials
and optimizing operating parameters

Baharuddin Bin Ali
Agri-THERM's Mobile Pyrolysis Pilot Plant
119
Ready to be
relocated
Ready for
action
119
Dorchester, Ontario, Canada N0L 1G5
• Agricultural waste is a light density, large volume product and is seasonal
in nature. Therefore, it is preferable to have a mobile pyrolysis plant that
can be transported to the source of the waste product.
• Agri-THERM have designed and built a mobile pilot plant with the
capacity of processing 10 – 40 Tonne/day of agricultural waste.

Baharuddin Bin Ali
Pyrolysis and Gasification Factsheet
120
• Pyrolysis and gasification, like incineration, are options for recovering value
from waste by thermal treatment. The basic technology concepts are not
novel but, several new proprietary processes have been developed.
What are Pyrolysis and Gasification ?
• Both pyrolysis and gasification turn wastes into energy rich fuels by heating
the waste under controlled conditions. Whereas incineration fully converts
the input waste into energy and ash, these processes deliberately limit the
conversion so that combustion does not take place directly. Instead, they
convert the waste into valuable intermediates that can be further processed
for materials recycling or energy recovery.
Pyrolysis:
• Thermal degradation of waste in the
absence of air to produce char,
pyrolysis oil and syngas, eg the
conversion of wood to charcoal
Gasification:
• Breakdown of hydrocarbons into a
syngas by carefully controlling the
amount of oxygen present, eg the
conversion of coal into town gas

Baharuddin Bin Ali
Why use Pyrolysis and Gasification ?
121
1. Increased possibilities for recycling
• Pyrolysis and gasification offer more scope for recovering products
from waste than incineration. When waste is burnt in a modern
incinerator the only practical product is energy, whereas the gases,
oils and solid char from pyrolysis and gasification can not only be
used as a fuel but also purified and used as a feedstock for petro-
chemicals and other applications.
• Many processes also produce a stable granulate instead of an ash
which can be more easily and safely utilised. In addition, some
processes are targeted at producing specific recyclables such as
metal alloys and carbon black. From waste gasification, in particular,
it is feasible to produce hydrogen, which many see as an increasingly
valuable resource.
• While this type of recycling is rarely economically attractive under
current market conditions, these technologies do offer the scope for
increasing recycling rates to achieve government targets or address
environmental concerns.

Baharuddin Bin Ali
Why use Pyrolysis and Gasification ?
122
2. Better energy efficiency & contribution to reducing global warming
• Gasification can be used in conjunction with gas engines (and potentially gas turbines)
to obtain higher conversion efficiency than conventional fossil-fuel energy generation.
By displacing fossil-fuels, waste pyrolysis and gasification can help meet renewable
energy targets, address concerns about global warming
• Conventional incineration, used in conjunction with steam-cycle boilers and turbine
generators, achieves lower efficiency.
• For technical and financial reasons, many current projects do not implement these
advantages, preferring instead to use proven – but lower efficiency – methods of
energy recovery integration with composting and materials recovery
• Many of the new processes fit well into a modern integrated approach to waste
management.
3. More flexibility of scale
• Systems are being developed for a wide range of capacities.
• Small scale (30,000 tonne/year) systems handle wastes generated by isolated
communities, while large (150,000 – 500,000 tonne/year) systems serve regional
facilities.

Baharuddin Bin Ali
What types of waste can be processed ?
123
• Gasification and Pyrolysis technologies can handle a very wide range of
materials (over 50 different types of waste for which systems are available
or under development).
• Specific processes have been optimised to handle particular feedstock
(for example, tyre pyrolysis and sewage sludge gasification), while others
have been designed to process mixed wastes like MSW. Today, the main
applications are:
• Processing agricultural and forestry residues
• Handling household and commercial waste
• Recovering energy from residues left from materials recycling (auto-
shredder residue, electrical and electronic scrap, tyres, mixed plastic
waste and packaging residues)
• Materials recycling and composting cannot handle mixed waste feeds –
today only landfill and incineration can do this.
• A few pyrolysis and gasification systems can handle unsegregated MSW,
although operational reliability has not yet been fully demonstrated for
most of these processes.

Baharuddin Bin Ali
What processes are available commercially ?
124
•More than 150 companies are marketing systems
based on pyrolysis and gasification concepts for
waste treatment. Many of these are optimised for
specific wastes or particular scales of operation.
•Today, about 10 companies are vying for the
largest potential market, bulk disposal of MSW.

Baharuddin Bin Ali
Is this technology proven in operation ?
125
• More than 100 facilities operating or ordered around the
world, capable of processing over 4 million tonnes of
waste per year.
• Some plants – particularly in Europe and Japan - have
been operating commercially for more than 5 years.
• Many of the proprietary systems currently being
promoted have only operated so far as small scale pilots
and, in general, incineration is far more proven than
pyrolysis and gasification for most applications.
• There are of course concerns about operational reliability.

Baharuddin Bin Ali
How do the economics compare with alternatives ?
126
• Shortage of hard data on true CAPEX and OPEX for 'real-
world' applications (many projects have been supported by
subsidies while, in other cases, vendors have forward-priced
projects to secure prestigious references.
• Gasification and pyrolysis have been proven commercially
feasible.
• But project costs are rarely significantly lower than
conventional alternatives. Individual projects need to be
considered on a case-by-case basis to determine economic
viability.

Baharuddin Bin Ali
Pyrolysis and Gasification for handling unsegregated MSW
127
• Focus is on the potential for these technologies to handle the
bulk disposal of household waste. Several commercial sites in
Japan.
• Technical and economic feasibility not fully demonstrated.
• Increasing emphasis upon resource recovery and renewable
energy may make these processes more attractive in the
medium term.
• The key to their widespread adoption will be successful
extended operation at 'flagship' reference facilities.

Baharuddin Bin Ali
Principles of Pyrolysis
128
Mode Conditions Liquid Char Gas
Fast
pyrolysis
moderate temperature,
short residence time
particularly vapour
75% 12% 13%
Carbonisatio
n
low temperature, very long
residence time
30% 35% 35%
Gasification
high temperature, long
residence times
5% 10% 85%
• Pyrolysis is thermal decomposition occurring in the absence of oxygen. It is always also the first
step in combustion and gasification processes where it is followed by total or partial oxidation
of the primary products.
• Lower process temperature and longer vapour residence times favour the production of
charcoal.
• High temperature and longer residence time increase the biomass conversion to gas and
moderate temperature and short vapour residence time are optimum for producing liquids.
• The product distribution obtained from different modes of pyrolysis process are summarised in
the table below. Fast pyrolysis for liquids production is of particular interest currently as the
liquids are transportable and storage.
Typical product yields (dry wood basis) obtained by different
modes of pyrolysis of wood

Baharuddin Bin Ali
Fast Pyrolysis
129
1. Fast pyrolysis occurs in less than few seconds. Therefore chemical reaction kinetics, heat and
mass transfer processes, and phase transition phenomena, play important roles. The critical
issue is to bring the reacting biomass particle to the optimum process temperature and
minimize its exposure to the intermediate (lower) temperatures that favour formation of
charcoal either:
1. by using small particles, eg: in the fluidised bed processes, or
2. to transfer heat very fast only to the particle surface that contacts the heat source,
which is applied in ablative processes.
2. In fast pyrolysis biomass decomposes to generate mostly vapours and aerosols and some
charcoal. After cooling and condensation, bio-oil is formed which has a heating value about
half that of conventional fuel oil. While it is related to the traditional pyrolysis processes for
making charcoal, fast pyrolysis, with carefully controlled parameters gives high yields of bio-
oils. The essential features of a fast pyrolysis process for producing bio-oils are:
• very high heating and heat transfer rates at the reaction interface, which usually requires a
finely ground biomass feed
• carefully controlled pyrolysis reaction temperature 500ºC and vapour phase temperature of
400 - 450ºC,
• short vapour residence times of typically < 2 seconds
• rapid cooling of the pyrolysis vapours to give the bio-oil product.

Baharuddin Bin Ali
Fast Pyrolysis
130
3. The main product, bio-oil (75% wt on dry feed basis). By-products char and gas
which are used within the process to provide the process heat requirements so
there are no waste streams other than flue gas and ash.
4. A fast pyrolysis process includes drying the feed to typically < 10% water in
order to minimise the water in the product liquid oil (< 15% acceptable),
grinding the feed (2 mm in the case of fluid bed reactors) to ensure rapid
reaction, pyrolysis reaction, separation of solids (char), quenching and
collection of the liquid product (bio-oil).
5. Virtually any form of biomass can be considered for fast pyrolysis. Nearly 100
different biomass types have been tested by many laboratories ranging from
agricultural wastes.
6. At the heart of a fast pyrolysis process is the reactor. Although it probably
represents at most only about 10-15% of the total capital cost of an integrated
system, most R & D has focused on the reactor, followed by control and
improvement of liquid quality including improvement of collection systems.
7. The rest of the process consists of biomass reception, storage and handling,
biomass drying and grinding, product collection, storage and, when relevant,
upgrading.

Baharuddin Bin Ali
Overall Fast Pyrolysis Process
131
1. Reception and storage
• Low capacity systems of < 3 t/h feed typically consist of a concrete pad for
tipping delivered feed and a front end loader to move it between reception,
storage and handling steps.
• Larger size plants require more sophisticated systems employs weighbridge,
tipping units, conveyors, bunker storage.
2. Feed drying
• Usually essential unless a naturally dry material such as straw is available (< 10%
moisture). The feed moisture report to the liquid product but also the reaction
water from pyrolysis, (typically gives 12-15% water) in the product.
• Waste low grade process heat would usually be employed.
3. Comminution
• Particles have to be very small to fulfil the requirements of rapid heating and to
achieve high liquid yields.
• This is costly and reactors that can use larger particles, such as ablative
pyrolysers, have an advantage.
4. Reactor
• various configurations have been tested that show considerable diversity and
innovation in meeting the basic requirements of fast pyrolysis. The "best"
method is not yet established.

Baharuddin Bin Ali
Overall Fast Pyrolysis Process
132
Overall fast pyrolysis process (continue)
5. Char + ash separation
• Some char is inevitably carried over from cyclones and collects in the liquid.
Almost all of the ash in the biomass is retained in the char. So successful char
removal gives successful ash removal.
• The char may be separated and exported, otherwise it would be used to provide
process heat either directly as in circulating fluid bed reactors or indirectly as in
fluid bed systems .
6. Liquids collection
• Larger scale processing would usually employ quenching with an immiscible
liquid such as a hydrocarbon or cooled liquid product. Although collection of
aerosols is difficult there has been considerable success with electrostatic
precipitators. Careful design is needed to avoid blockage from differential
condensation of heavy ends. Light ends collection is important in reducing liquid
viscosity.
7. Storage and transport
• The bio-oils require a tank farm for storage and later blending facilities. Both
storage and transport are features unique to fast pyrolysis and permit
economies of scale to be realised from building as large a conversion plant as
possible as well as offering economic supplies of bio-oil for distributed or
decentralised small scale power and heat applications.

Baharuddin Bin Ali
BIO-OIL - Pyrolysis Liquid
133
1. Crude pyrolysis liquid or bio-oil is dark brown and approximates to biomass in
elemental composition of a very complex mixture of oxygenated hydrocarbons
with an appreciable proportion of water from both the original moisture and
reaction product. Solid char may also be present.
2. Bio-oil is formed by rapidly quenching and thus ‘freezing’ the intermediate
products of flash degradation of hemicellulose, cellulose and lignin. Bio-oil thus
contains many reactive species, which contribute to its unusual attributes. Bio-oil
can be considered a micro-emulsion in which the continuous phase is an
aqueous solution of holocellulose decomposition products, that stabilizes the
discontinuous phase of pyrolytic lignin macro-molecules through mechanisms
such as hydrogen bonding. Aging or instability is believed to result from a
breakdown in this emulsion. In some ways it is analogous to asphaltenes found in
petroleum.
3. Fast pyrolysis bio-oil has a higher heating value of about 17 MJkg-1 as produced
with about 25% wt. water that cannot readily be separated. Bio-oil will not mix
with any hydrocarbon liquids. It is composed of a complex mixture of
oxygenated compounds that provide both the potential and challenge for
utilisation.

Baharuddin Bin Ali
BIO-OIL - Pyrolysis Liquid
134
4. Bio-oil has a distinctive odour - an acrid smoky smell, can irritate the eyes on prolonged exposure
due to the low molecular weight aldehydes and acids. It contains several hundred different
chemicals in widely varying proportions, ranging from formaldehyde and acetic acid to complex
high molecular weight phenols, anhydrosugars and other oligosaccharides.
5. Bio-oil contains varying quantities of water, which forms a stable single phase mixture, ranging
15 wt% to 30 - 50wt% water, depending on how it was produced and subsequently collected.
Pyrolysis liquids can tolerate the addition of some water, before phase separation occurs. It
cannot be dissolved in water. It is miscible with polar solvents such as methanol, acetone, etc. but
totally immiscible with petroleum-derived fuels.
6. The density of bio-oil is very high at around 1.2 kg/litre (light fuel oil 0.85 kg/litre), meaning the
liquid has 42% of the energy content of fuel (weight basis), but 61% (volumetric basis). This has
implications on the design and specification of equipment such as pumps and atomisers in boilers
and engines.
7. The viscosity of the bio-oil as produced can vary from 25 - 1000 cSt (at 40°C) or more depending
on the feedstock, the water content of the oil, the amount of light ends that have been collected
and the extent to which the oil has aged.
8. Bio-oils cannot be completely vaporised once they have been recovered from the vapour phase.
If bio-oil is heated to > 100ºC it rapidly reacts and eventually produces a solid residue of around
50 wt% of the original liquid and some distillate containing volatile organic compounds and water.
While bio-oil has been successfully stored for several years in normal storage conditions in steel
and plastic drums without any deterioration that would prevent its use in any of the applications
tested to date, it does change slowly with time, most noticeably there is a gradual increase in
viscosity.

Baharuddin Bin Ali
Typical properties of wood derived crude bio-oil
135
Physical property Typical value Characteristics
Moisture content 20-30%
pH 2.5
Specific gravity 1.20
Elemental analysis
C 55-58%
H 5.5-7.0%
O 35-40%
N 0-0.2%
Ash 0-0.2%
HHV as produced 16-19 MJ/kg
Viscosity (40oC & 25% H2O) 40-100 cp
Solids (char) 0.1 – 0.5%
Vacuum distillation residue <50%
· Liquid fuel
· Ready substitution for conventional
fuels in many stationary applications
such as boilers, engines, turbines
· Heating value of 17 MJ/kg at 25% wt.
water, is about 40% that of fuel oil /
diesel
· Does not mix with hydrocarbon fuels
· Not as stable as fossil fuels
· Quality needs definition for each
application

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