edgard.gnansounou the bio-refinery concept contacts process synthesis and life cycle assessment @...
TRANSCRIPT
edgard.gnansounou
The bio-refinery Concept
Contacts
Process Synthesis and Life Cycle Assessment
@
Edgard Gnansounou+41 (0)21 / 693 06 27
epfl.ch
Laboratory of Energy SystemsStation 18 EPFLCH-1015 Lausanne lasen.epfl.ch
09.11.2007 2 LASEN
Co-production in Biofuels chains: Potential of the sugar-lignin platform
Hemicellulose(Pentosans-Xylan)
Cellulose(Hexosans-Glucan)
Lignin
BiomassPre-treatment
SugarsC5/C6 sugars
(Xylose-Glucose)
Xyiytol Chemical pathway from pentoses
Direct Product use
Non-nutritive sweetenerBuiding block for Xylaric acid, glycols
Sorbitol Chemical pathway from hexoses
Non-nutritive sweetenerBuilding block for Isosorbide, propylene
glycol
Product’s derivatives use
Antifreeze, unsaturated polyester resins
PET like polymers, anrifreeze, water soluble polymers for water treatment
HO
OH
OH
OH
OH
OH
OH
OH
OH
OHHO
Levulinic acid Chemical pathway from hexoses/
pentoses
Building block for Methyl tetrahydrofuran, butyrolactone,
Diphenolic acid
Fuel oxigenates, pesticedes,solvents, polycarbonate resins
O
O
HO
Succinic acidBiotechnological pathway from hexoses
Building block for Butanediol (BDO),Tetrahydrofuran (THF), gamma-
Butyrolactone (GBL). pyrrolidones
Fibers such as Lycra, green solvents, water soluble polymers for water
treatmentHO
O
O
OH
3-Hydroxypropionic acidBiotechnological pathway from hexoses
Building block for 1,3 propane diol, acrylates
Sorona Fiber, contact lenses, super adsorbant polymers (Diapers)HO OH
O
EthanolBiotechnological pathway from hexoses/
pentoses
Fuel for transport, Building block for Ethylterbutylether (ETBE), ethyl esters
Fuel, Fuel Oxigenate,
Ferulic acidBiotechnological pathway from lignin by
enzymatic depolymerizationBuilding block for vanilin, polymers Flavouring agents, phenolic resins
O
OH
O
HO
OH
Furfural Chemical pathway from pentoses
Solvent in petrochemical refining, Building block for Tetrahydrofuran
(THF), Nylon 6 Nylon 6,6Thermoplastic fibers, resins, solvents
O
H
O
Lactic acidBiotechnological pathway from hexoses
Building block for polylactides such as polylactide acid (PLA)
Biodegradable Polyethylene-like polymers
OH
OH
O
Sulfur-free solid fuelPelletization of lignin rich solid residue
Fuel for heat and power generation
Product
09.11.2007 3 LASEN
Co-production in Biofuels chains: The allocation issue in the bio-refinery concept
Axis 2 Process synthesis and
Optimization
Rigorous material and energy balances are needed to improve relevance of LCA outputs and refine cost estimation
Production function is no necessarily linear and plant size influence in overall techno-economical and environmental viability must be investigated
A multicriteria optimization approach taking into account economical and environmental sustainability factors is needed
A bio-refinery is a process in which biomass conversion leads to a multifunctional system including fuels, value added chemicals and power generation.
Axis 1 Allocation
In the LCA framework, the allocation of environmental burdens between co-products becomes crucial
Production volume, function and market value varies greatly among co-products allocation
Some biorefinery products does not have an established market and
09.11.2007 4 LASEN
Allocation StrategiesStrategy Characteristics Pertinence
SubdivisionReduces system complexity by separate it into sub-processes.
Generally it is not possible to completely avoid allocation Sub-processes must be separated in space or in time.
System expansion
(allocation by substitution)
Recommended by ISO-14044 as a first choice method to avoid allocation
Consist of assigning to the co-products environmental burdens of products with equivalent functions
Function equivalent products do not necessarily have equal environmental burdens. Introduces uncertainty into LCA (ad infinitum substitution). Must include dynamic market evolution (consequential LCA)
Allocation by physical properties
According to ISO-14044 allocation must be done based in physical causalities when it is not possible to avoid it. Consists of determining factors to distribute environmental burdens between co-products according to a selected physical property (mass, energy content, carbon contents)Easy interpretation and implementation
Restricted to process where all co-products have similar function, i.e. energy content when all co-products are used as fuels Weight-based allocation could favor biofuels with high volume of co-products Is not always straightforward to determine a direct correlation with selected physical property
Allocation by economic value
Consist of determining factors for the distribution of environmental burdens between co-products according to the share on sales volume
It is pertinent if demand and search of profit are considered to be the driving factor for productionIf market value is used as the allocation criterion, time dynamics becomes important as in the case of substitution (Price variability, subsidies and other market distortions)Does not necessarily reflect physical reality.
09.11.2007 5 LASEN
Ongoing research and questions Research Axis 1 Allocation
– What allocation method is suitable for a multifunction process such as a bio-refinery
– Is market value an adequate criterion when allocation is based on economic principles?
– Should the social utility of a co-product be used instead of market value for allocation?
– What are the trade-offs between improving the significance of LCA conclusions and the operability of the methodology?
Research Axis 2 process design– Develop a Modular Platform for
Integrated Assessment of Lignocellulosic Biochemical Refineries (LCBR-MPIA), using process engineering software and multicriteria optimization algorithms.
– Coupling process modeling and optimization with LCA development
– Evaluate different technological options to increase functionality of Biofuels production
Ligno-cellulosic feedstock
Biomass fractionationCatalist, steam, acid, enzyme etc
Hemicellulose(pentoses, hexoses)
Xylose
Xylite
Furfural
Furan resines
Nylon 6,6
Nylon 6
Lignin (phenol polymer)
Ligninases, lignin peroxydases, laccases, etc
Natural binder and adhesives
Sulfur free solid fuel
Sub-bituminous coal
Cellulose(Glucose polymer)
Enzimatic depolimerization
Mono aromatic hydrocarbons
Flavouring agents, polycarbonates, resins
Glucose (hexose)
Hydrolysis
Fermentation products:
· Fuels· Organic acids (lactic acid)· Solvents (acetone, butanol)
HMF, Levulinic acid
Softner+solvents
Softner+solvents
Softner+solvents
Laboratory of Energy Systems (LASEN)
Station 18 EPFLCH-1015 LausanneSwitzerland