Kraftstoffe aus Abfällen - eine Problemdiskussion

Transcription

1 Kraftstoffe aus Abfällen - eine Problemdiskussion 24. Juli 2008 Innovationspark Wuhlheide, Berlin Institut für olztechnologie und olzbiologie, amburg TB Dietrich Meier TB Content! Thermolysis of Biomass! Liquefaction processes! Product properties and applications! Upgrading! Summary 1

2 TB Amount of Principal Constituents in Plant Materials thers Cellulose emicell. Lignin 20 0 Laubholz Nadelholz Einjahrespflanzen ardwoods Softwoods Straws TB Products of Fast Pyrolysis of Cellulose (Avicell( Avicell) (Py-GC/MS) C C --- C2 TIC: [BSB1]AVICELL.D C2 --- C2 C 4 C 2 C 2 3C C C C a C C C b 3C C C C c C 3C d C 3C C C a bc d C C C C 3C C C min. 2

3 TB Structural Model of Beechwood Lignin 2 C C 2 C 2C C C C 2 C C C C 6 C C2 C C C 2C C3 2 C 5 C 25 C C C 3C 0.4 C3 5 2 C C C 3C C C 2C 3C C3 C3 C C C C 3C 3C C 3 C 2C C 2C 2C 14 C C3 4 C 12 C C C3 2C C C 3C C3 C3 C3 2 C C C3 C C C3 2C 2C 3C C3 C3 2C C 2C C C C C C 8 C C C2 C C C C2 C C C C2 21 3C 2C C 19 C 3C C3 7 C C C 3C C3 C2 C C C C C C3 3C 2C 2 C 3C C C C C 2 C2 C C2 C C C C C C C2 C C C3 3C C3 C C C3 C3 nach Nimz, Angew. Chem. internat. Edit., 13, TB Products of Fast Pyrolysis of Lignin (Beech( MWL) by Py-GC/MS 2 C 2 3C 3 C C R 2 S C 3 R 1 R 2 G C 3 R 1 syringyl guaiacyl TIC: [BSB1]MWLBU.D G C3 G C3 C3 C3 C C3 C2 C G G C3 S C3 C3 C2 C S C3 C S C3 C3 C3 C3 C C S C2 C C G C3 C3 C3 C C C S C3 C3 C2 C C S C3 C C C RT (min) 3

4 TB Product Distribution of Thermolysis Processes Process Fast Pyrolysis Medium temperature (400 C C) Short residence times (~ 1 s) Liquid Coke 75 % Products 12 % Gas 13 % Charcoal production Low temperature ( C) long residence times (several hours) 30 % 35 % 35 % Gasification igh temperatures (800 C C) variable residence times (10 s - 30 min) 5 % 10 % 85 % TB Liquefaction Methods! igh-pressure liquefaction! Atmospheric-pressure fast pyrolysis 4

5 TB igh Pressure Liquefaction Processes! beginning ca. 1920, USA, SE, DE (coal)! ca PERC and LBL process, USA! ca TU, NL TB igh Pressure Liquefaction of Biomass with the PERC-Process ( ) " Slurry made of wood, bio-oil and alkali (5%); 7.5 / 67.5 / 25 wt.%) Pittsburgh Energy Research Center, USA " Synthesis gas ( 2 /C) for reduction " Yields: "40-55 % bio-oil "1 % char ( C) min. 200 bar " Advantages: "relatively high oil yields "satisfactory operation " Disadvantages: "requires milling and drying "low wood concentration "high consumption of syngas 45-55% Na 2 C 3 5

6 TB igh Pressure Liquefaction of Biomass with the LBL Prozess ( ) " Slurry made of wood and diluted sulfuric acid (0,07 %), p 1.7 " 180 C for 45 min., homogenisation with Na 2 C 3 to p 8 " Aqueous slurry (approx. 20 % soldis) as reactor feed " Yields: " approx.: 30 % bio-oil " approx.: 1 % char Lawrence Berkeley National Laboratories, CA, USA 180 C 45 min bar 5-60 min. " Advantages: " neither milling nor drying " no consumption of reducing gasers " Disadvantages: " Large water volumes " low concentration of organics " rel. low oil yields TB LBL-Product Description The crude oil product from direct wood liquefaction is a bitumen-like black material, which is liquid, but viscous, at slightly above ambient temperature. It has specific gravity in the range... The oil has been found to have oxygen contents in the range of 15 to 19%, typically 17%; hydrogen from 6.8 to 8%-..typically 7.3%-- and carbon from 74 to 78%--typically 76%. The gross heating value is about 34 MJ/kg. 6

7 TB igh Pressure Liquefaction ydro Thermal Upgrading (TU) Conditions: C; bar reaction time 5-20 minutes liquid water present Feedstocks: All types of biomass, domestic, agricultural and industrial residues, wood. Also wet feedstocks, no drying required Products 45 wt.% Biocrude 25 wt.% Gas (> 90% C2) 20 wt.% 2 10 wt.% dissolved organics Biocrude eavy organic liquid, solidifies at 80 C Not miscible with water xygen content %w, /C = 1.1 LV MJ/kg Separation into light and heavy fractions by flashing or extraction Light Biocrude Contains no minerals, can be upgraded by D eavy Biocrude Co-combustion in coal power station green electricity Gasify: green hydrogen Thermal efficiency: % University Twente Dragan Knezevic, Prof. W. van Swaaij Quarz Capillaries Feed: (water +) wood; temperature = 340 C Feed 100 kg/h (wet), biocrude 8 kg/h TB Fast Pyrolysis: Thermodynamic Requirements for igh Liquid Yields! igh heating rates! igh mass transfer rates! Narrow temperature window! Rapid cooling (quenching) 7

8 TB Typical Mass Balance of Fast Pyrolysis Processes Yield [wt.%] kg Wood Temperature [ C] oil gas char Reactor: 475 C 1 s kg il kg Gas kg Char Energy Densities (GJ/m 3 ): Straw 2 Wood chips 8 Char 9 Pyrolysis oil 20 TB Development of Fast Pyrolysis Processes! Univ. Waterloo, BFB, 1981 report to government => Spain => RTI =>Dynamotive (Canada)! Univ. Western ntario, CFB, => Ensysn (Canada) (food flavouring) - scaled up in Italy! NREL, Aston Univ., ablative reactors, Univ.Twente => BTG, vti (BF) => PYTEC! Univ. Laval => Pyrovac (pyrolysis in vacuum) 8

9 TB Reactor Configurations for Fast Pyrolysis circulating fluidized bed fixed bed oil hot cyclone sand loop biofuel sand bed from char combustor excess gas char hot cyclone pneumatically fluidised biofuel recycle gas recycle gas recycle gas rotating cone char twin char combustor twin screw hot cyclone condenser biofuel sand loop oil excess gas oil, gas sand loop char combustion gas heater in sand loop mechanically fluidisied condenser hot cyclone biofuel oil char ablation cold biofuel vacuum biofuel vapour hot disc see also vortex reactor rotating hot disc, cylinder, blade direct contact gas molten salt vacuum tank char oil Current Fast Pyrolysis Processes TB! BioThermTM,! RTPTM, Ensyn, CAN (70 tato)! Rotating Cone, Dynamotive, CAN (100 tato) BTG, NL (50 tato)! BioLiq, FZK, DE (12 tato)! BT, PYTEC, DE (6 tato, 48 tpd) 9

10 TB Transport and Utilisation of Dynamotive s Bio-il First commercial transport of Dynamotive s Bio-oil renda s gas turbine 2,5 MW with oil tank Completion of a new 200 tpd plant at Guelph, ntario, CAN Privately owned by Evolution Biofuels, a subsidary of Megacity Recycling Feedstock: construction, demolition wood The products will be biooilplus (BP) - biooil mixed with 22 % char TB RTP TM Technology of ENSYN! 6 commercial plants in operation! 2000 t Bio-oil per month, mainly for liquid smoke aroma! largest plant: 80 tpd 50 tpd RTP TM plant 40 tpd Rhinelander, two plants Chemicals from bio-oil 10

11 TB BTG s Rotating Cone Technology Ash Gas Biomass Sand Vapours Sand & Char Air il Pyrolysis reactor Char Combustor Bio-oil Condensor TB BTG Plant from Genting (Malaysia), 50 tpd! Feedstock: empty fruit bunch (EFB) of palm, fibrous, wet (65%), after drying low density material (80 kg/m3), particle size < 10mm, moisture content < 10 wt%! t oil produced! oil yields 45-60%! il utilisation: combustion in boiler! Challenges: pretreatment of EFB, overall heat integration, ash melting, and oil transportation EFB: 11

12 TB FZK BioLiq-Concept TB Key Technologies of the Bioliq Process LR- Sandcracker pilot flame fuel oxygen SS pressure shell water cooled radiation screen ~ 1300 C ~ 25 bar GSP-Gasifier raw syngas molten slag 12

13 TB PYTEC s s BT Process! Material: wood chips! Dryer: entrained flow! Disk diameter: 1200 mm! Temperature max: 700 C! Rotation speed: 60 rpm! eating: 100 kwel! Control: Siemens S7 SPS! Ablation rate: 3 mm/s TB BT-Pilot Plant in Bülkau 1 opper 2 Dryer 3 Pyrolyser 4 Condensation 5 CP

14 TB verall Composition of Fast Pyrolysis Liquids TB Typical Properties of Bio-ils Bio-oil Rape seed oil eavy fuel oil Density [g/cm 3 15 C] Viscosity [mm 2 15 C] Water [%] LV [MJ/kg] Ash [%] Elemental composition - C [%] [%] [%] N [%] 0.1 < S [%] <0.1 <

15 TB Utilization Pathways for Pyrolysis Liquids Bio-il thermal chemical gasifier boiler gas turbine, diesel engine fractions components syngas heat power liquid smoke, adhesives, fertilizer aldehydes phenols, levoglucosan transp. fuel TB Engines PYTEC 400 kwe Mercedes Benz motor in a CP plant 15

16 TB Elemental Composition and eating Values of Fossil Fuels, Biomasses and Conversion Products TB Bio-oil Yields vs. Upgrading Efforts Bio-oil yields Upgrading efforts heating fuel stationary engines transport fuels 16

17 TB Upgrading Methods for Liquids from Thermochemical Conversion! Physical upgrading in-line # catalytic pyrolysis # hot gas filtration # staged condensation off-line # micro-emulsion # blending # gasification! Chemical upgrading (oxygen removal, molecular weight reduction, minimization of 2 consumption) heterogeneous catalysis in fixed-bed reactors # Ni, Mo, Co, Cr # precious metals slurry-phase catalysis TB Chemical Upgrading with Liquefaction Products! PNL, PNNL, USA: eterogeneous catalytic hydroprocessing igh pressure products => single stage ( wt.% oxygen) Bio-oils from fast pyrolysis => two stage => 2-3 wt.% oxygen, 0.5 L/L product.! VEBA, DE: eterogeneous catalytic hydroprocessing Bio-oils from fast pyrolysis => 0.02 wt.% oxygen, 5 wt.% hydrogen consumption.! DMT FuelTec, DE: IGR technology Bio-oils from fast pyrolysis => <0.1 wt.% oxygen, 34 % yield. Elliott, D.C., Energy & Fuels, 21, 2007, : The potential for competetive costs in the fuels marketplace with the recent increase in petroleum prices needs to be evaluated. 17

18 TB EU Integrated Project BICUP ( ) 17 partners 8 countries TB Summary (1)! Wide variety of reactor configurations. The "best" method is not yet established.! The liquid bio-oil product has the considerable advantage of being storable and transportable as well as the potential to supply a number of valuable chemicals.! Fluid beds offer robust and scalable reactors, but the problem of heat transfer at large-scales in not yet proven. Circulating fluid beds and transported beds may overcome the heat transfer problem but scaling is not yet proven and there is an added problem of char attrition.! Mechanical devices such as ablative and rotating cone reactors offer advantages of compactness and absence of fluidising gas, but may suffer from scaling problems and always the problems associated with moving parts at high temperature. 18

19 TB Summary (2)! There are specific challenges facing liquefaction products that relate to technology, product and applications including: Cost of bio-oil, which is 10% to 100% more than fossill fuel. Availability: there are limited supplies for testing and development of applications. There is a lack of standards for use and distribution of bio-oil and inconsistent quality inhibits wider usage. Bio-oil is incompatible with conventional fuel. Users are unfamiliar with this material, and dedicated fuel handling systems are needed. TB Summary (3)! Pyrolysis processes (%: 35-40%) Fast Pyrolysis => Bio-oil => direct combustion in boilers => heat & power Fast Pyrolysis => Bio-oil + co-solv. => adopted stationary Diesel engines (CP), or adopted gas turbine => heat & power Fast Pyrolysis => Bio-oil + D => hydrcarbon-like => refinery => transport fuel! igh-pressure processes (%: %) PERC, LBL, TU => Bio-Crude (highly viscous) =>refinery => transport fuel 19

20 TB Summary (4)! No direct liquefaction process gives transport fuels! All products from direct liquefaction processes need further upgrading to be used as transport fuel 20