PROCESS DEVELOPMENT AND SIMULATION FOR PRODUCTION …

1International Freiberg Conference on IGCC & XtL Technologies 16-18/06/2005

PROCESS DEVELOPMENT AND SIMULATION FOR PRODUCTION OF

FISCHER-TROPSCH LIQUIDS AND POWER VIA BIOMASS GASIFICATION

Guillaume Boissonnet - CEA Grenoble

Nicolas Boudet - IFP Lyon

Jean-Marie Seiler – CEA Grenoble

Sylvie Rougé – CEA Grenoble

Commissariat à L’Énergie Atomique – Institut Français de Pétrole


CONTEXTSituation of France considering BtL

Context Preliminary analysis ConclusionProcesses


Energy in France

w France: Commissariat au Plan "Énergie 2010-2020"– Energy demand multiplied by 3 between 1960 and 2000 – In 2020: Energy demand in France

Ä +9 % (S3) to +37 % (S1) compared to 1997.

– Transport sector: the most important increaseÄ Up to + 57 % (S1), the increase of other sectors is moderated.

222,2257,7279,4204,5TOTAL

59,371,678,650,2Transports

97,8112,7124,693,2Build. + Service

65,173,476,261,1Industry + Agric.

2020S3

2020S2

2020S1

1997MtoeEnergy demand in France (Mtoe)

1960 1966 1972 1978 1984 1990 1996 2002 2008 2014 2020

S1S2

S3

0

50

100

150

200

250

300

Mto

e

+43%

+20%

Source: Commissariat du Plan "Énergie 2010-2020"



BtL & gasification main groups in Europe

w Germany– Choren, Future Energy, VW, Daimler Chrysler, FZK, …

w The Netherlands– ECN, Shell, Universitait Utrecht, Novem…

w Northern countries– Volvo, ChrisGas, VTT, TDU, TKE…

w European Project– Renew

w Alternative fuels contact group

French politics and industrialists move slowly !(Priority on EtBE & EMHV)



What is a good biofuelw It must be produced in large amounts

– Biomass resource abundant and easy to collect – No competition with food

w It must have lots of environmental advantages– Favourable CO2 balance– Reduced pollutants emissions (NOx, HC, CO, particles…)

w It is first a good fuel– Cetane number (gasoil) / octane number (gasoline)– Low aromatics fraction

w In Europe, it is preferably a diesel fuel directly useable in motor engines

BtL from lignocellulosic biomass



Industrial Biofuel Production

w Production of high grade diesel fuels with biomass gasification and Fischer-Tropsch synthesis

w Potential of production– from ~ 7 to 15 Mtoe/year in France (hyp. 50 Mt/year renewable

dry biomass - wood + agricultural residues)– ~13 to 27 % of fuel need for transportation (~55 Mtoe annual)

– No sulfur– No aromatics– High cetane number– Fuel adapted to new combustion technologies

Gasification

SynGas

Cleaning Synthesis

Fuel

Energy

Biomass

H2O, O2



PRELIMINARY ANALYSISOur way to approach the problem



Calculation at thermodynamic equilibrium for STEAM gasification (reference case)

w Stoichiometric conditions at atmospheric pressure. w Reaction (ideal): C6H9O4 + 2H2O -> 6CO + 6.5 H2

w Composition of gases

0

1

2

3

4

5

6

7

8

500 600 700 800 900 1000 1200 1300 1400T( °C)

Mol

e nu

mbe

r

C solide

H2

CO

CO2

CH4

H2O

H2/CO

Optimum yield zoneTechnically feasible



Conclusions of the thermodynamic approach

w Temperature for ideal transformation of biomass into CO + H2is at least 1000°C at 1 bar

– at 10 bars: 1300°C !

w Below 1000°C CH4 is produced

w Enthalpy of reaction: C6H9O4+2H2O => 6CO+6,5 H2

– ~ 6,2 MJ/kg Dry Biomass

w Gasification requires energy above 600°C– process will generate energy at low temperature (< 300 °C) that

will be difficult to reuse in the process (electricity generation is possible)



The maximum CO+H2 production reaction

Idealized

reactions !

Combustion requires ~ 2C & 2 H2

available: 4 CO + 4,5 H2

Shift

1,5 CO => 1,5 H22,5 CO + 6 H2

After synthesis: max 2,5 CH2Final (minus losses): ~1,5 CH2,

Mass yield ~ 15%

available 6 CO + 6,5 H2

Shift

2 CO=> 2 H24 CO 8,5 H2

4 CH2~3 CH2

Mass yield ~30 %

6 CH2~ 5 CH2

Mass yield ~ 48 %

Autothermal route Allothermal (external energy)

synthesis requires: H2/CO ~2for FT, DME and Methanol

H2/CO ~1 if FT Iron catalyst


No shift, but

external H2 input

6 CO 12 H2

C6H9O4 + 2 H2O => 6 CO + 6,5 H2 Endothermal reaction


58%

30%

15%

TheoreticalMaximum

Theoretical yields

0,25 CH2

CH2

0,5 CH2

CO+1,1H2

100%

50%

25%

Carbonyield

Massyield

0,43

LHV (MJ)

0,54

0,63

0,16

0,32

Autothermal

Allothermal without

additional hydrogen

Allothermal with additional

hydrogen

Steam

Gasifica

tion

Synthesis

Pyrolysis +

hydrodeoxygenation

Synthes

is

Synthesis


CH1,5O0.66


Beyond Thermodynamics

w Considering Kinetics– Yields considering kinetics equivalent to yields at the equilibrium

with a 200°C lower temperature– CH4: kinetic rate of reforming or cracking is about zero– Solid residue: steam gasification kinetic is very low– Tars come from kinetic competition between reactions

w Considering Energy losses– Energy recovery is not ideal– Low temperature energy is lost

w Considering primary energy for endothermal steam gasification

– Using oxygen lowers the overall mass yield (a part of biomass is burnt as primary energy)

– Using other primary energies must be CO2 free



PROCESSESKey points and Analysis



treatment

Pyr

olys

isG

asifi

catio

n

Entrained or fluidized bed

High temperature stage

Allo/Auto

Pyrolysis, densification

Fixed bed or entrained flow

reactorHigh temperature

Allo / Auto

T (°C)

0

200

400

600

800

1000

1200

Heat Exchanger Cleaning

Shift

Synthesis

Possibility of using waste

1400

Synthesis gas (CO, H2)

Biomass preparation


Low Temperature


Key points

w Decentralisation– Optimum for Synthesis section economics: 1 train FT (slurry reactor Ø10m)

Ä 15 000 bbl/j gasoil = 60-70 t/h means 300 t/h dry biomass (mass yield = 20%)Ä Theoretically: 20 industrial sites in France (4-5 sites if 5 FT synthesis trains)

è a decentralised first step of energy densificationw Pressure

– Disadvantage on a thermodynamical point of view– May be an advantage in terms of kinetics (gas/solid reaction)– Advantage for the rest of the process (around 30 bars for FT synthesis ;

around 80 bar for methanol synthesis): avoiding compressionw Without N2 because Inert gas leads to

– a high price for energy balance (thermal, compression)– Oversizing

w Pollutants (organics, inorganics, aerosols)– Tars: avoided with very high temperature processes– Gaseous inorganics compound (wall corrosion, catalysts poisoning):

removed at low temperatureCleaning means low temperature

w Recycling– FT synthesis: by products (Tail Gas, Naphtha) may be recycled to increase

the overall mass yield (reforming)



Cases A & B: Fluidised bed

Combustion950°C

Gasification800°C4bars

Air CH4

Solid

Steam

HT Stage1300°C

Cleaning Compression

WaterGasShift

CO2Removal

FT synthesis+

HydrocrackingTurbine

KeroseneGasoil

NaphthaWet Bio-mass 40%Drying

Purge

TailGas

Case A

Case B1

Case B1

Case B2

Case B3

Case B


Case A: Fluidised Bed onlyCase B: Fluidised Bed + Allothermal HTS

1: without recycling2: Tail gas recycling3: Tail gas + Naphtha recycling


Cases C & D: Entrained Flow Reactor

Gasification1400°C

Auto: 30 barsAllo: 5 bars

O2 Steam

HCReforming


WaterGasShift

CO2Removal

FT synthesis+


KeroseneGasoil

NaphthaWet Bio-mass 40% Drying

Purge

TailGas

Case C1

Case C1Case D1

Case C2

Case C: Autothermal (O2)Case D: Allotherrmal (electricity)

Case C2

Case D2



Case E: Rapid Pyrolysis + Entrained Flow Reactor

Gasification1400°C30 bars

O2 Steam

HCReforming


WaterGasShift

CO2Removal

FT synthesis+


KeroseneGasoil

NaphthaWet Bio-mass 40%

RapidPyrolysis

TailGas



Hypotheses

w Case A & B– Gasification reaction: out of equilibrium (H2/CO=1.8 if a right catalyst)– High temperature stage: equilibrium at 1300°C,

w Case C, D & E– Gasification reaction: equilibrium at 1400°C

Ä C: steam + oxygenÄ D: steam + electricity

– E: Pyrolysis products 10% gas ; 90% slurry

w Overall FT+HDK reaction– Based on Cobalt catalyst

w Heat recovery efficiency: 80%w Electricity production efficiency

– Steam: 33% ; Gas turbine: 50%



Results for 50 to 300 t/h dry biomass

w Steps inducing energy losses– Quench with water,– Gas compression (work + low temperature at the compressor inlet)– Under 300-400°C unit operations: especially cleaning,– Electricity production with Gas turbine. An external inlet is better in terms of

mass and energy yield

~18523-2934-38D2Recycling allo Tail Gas (85%) + Naphtha (100%)

~ -10 (produced)27-33 (39-45)10-12 (16-20)EWithout

~12516-2216-20D1Without (electricity production at Gas Turbine)

039-4516-20C2Reforming auto Tail Gas (25%) + Naphta (100%)

~ -9 (produced)28-34 (40-46)11-13 (15-19)C1Without

~9428-3424-28B3HTS allo 85% Tail Gas + 100% Naphta

~6620-26 (30-36)15-19 (24-28)B2HTS allo 85% Tail Gas

~3319-25 (29-33)11-14 (17-21)B1Without

~ -7 (produced)20-26 (31-37)7-11 (11-15)AWithout

Inlet Electricity(Mwe)

Energy Yield(%)

C10+ (C5+)

Mass yield(%)

C10+ (C5+)CaseRecycling


0.5 to0.9 €/l

1 to1.3 €/l


Process Analysis

w Fluidised Bed without High Temperature Stage (HTS): not efficient enough.

w Fluidised Bed + Allothermal HTS or Entrained Flow Reactor– Same order of magnitude for yields– Tail gas recycling would be preferred

w Decentralised pyrolysis: to be studied with more details– +/- in term of mass and energy yield– Adding decentralised pyrolyse (no size effect on investment) may:

Ä Increase the part of pyrolyse in overall investmentÄ Increase the fuel price (to be confirmed)

w Allothermal Entrained Flow Reactor– Maximise the mass yield – With massive & low CO2, emissions electricity production.

w Auto / Allo: A choice between– Optimum for mass and energy yields– Maximise the fuel production



Lots of remaining Questions

w Biomass pre-treatment and injection– Way of densification: an energy analysis to be performed– Way of crushing– Injection under pressure

w Technical answers for gasification– Entrained Flow Reactors industrial reliability– Inorganics behaviour (solid/liquid/gas phases)– Pressure: mechanical issues at high temperature

w What is the best way for gas cleaning without loosing too much energy ?

– Filtration– Inorganics in gas phase

w FT Synthesis– Co or Fe catalyst ?

w Decentralisation?

Some ideasfor possible answers Work still in progress

Context Preliminary analysis Processes Conclusion


THANK YOU

[email protected]@ifp.fr

Commissariat à L’Énergie Atomique – Institut Français de Pétrole

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PROCESS DEVELOPMENT AND SIMULATION FOR PRODUCTION …