A. Poluzzi a, G. Guandalini a, I. Martínez* b, M. Schimd c, S. Hafner c, R. Spörl c, F. Sessa d, J. Laffely d, M.C. Romano a

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1 Sorption enhanced gasification (SEG) of biomass with CO2 capture for the production of Synthetic Natural Gas (SNG) and for transport sector with negative emissions A. Poluzzi a, G. Guandalini a, I. Martínez* b, M. Schimd c, S. Hafner c, R. Spörl c, F. Sessa d, J. Laffely d, M.C. Romano a a Politecnico di Milano, Department of Energy (Italy) b Instituto de Carboquímica, Spanish Research Council (CSIC) (Spain) c Institute of Combustion and Power Plant Technology IFK, University of Stuttgart (Germany) d Quantis (Switzerland) 14 th Greenhouse Gas Control Technologies conference, 21 st -25 th October, Melbourne (Australia) 1

2 OUTLINE Background: FLEDGED project and scope of the work Process description Performance index definition Results 2

3 Background: FLEDGED project and scope of the work Synthetic biofuels production from renewable energy sources like biomass has an important role to play in the decarbonized scenario needed in the coming years for fulfilling the 1.5ºC target Indirect gasification has a great potential due to its inherent advantages Using a CO2 acceptor as bed material: Sorption Enhanced Gasification results o Dual fluidized bed system using CaO as circulating bed material o Energy needed for gasification supplied by CaO carbonation ( CaCO3) and by sensible heat of circulating solids o Unconverted char leaving the gasifier supplies the energy needed in the combustor o The presence of CaO simplifies the syngas cleaning and purification section 3

4 Background: FLEDGED project and scope of the work OBJECTIVE FLEDGED: Develop a highly intensified and flexible process for production from biomass and validate it under industrially relevant environments (i.e. Technology Readiness Level 5 (TRL)) OBJECTIVE of this WORK: Solve the mass and energy balances of two synthetic fuel production plants based on sorption enhanced gasification, one focused on and other on Synthetic Natural gas (SNG), to compare their performance More info 4

5 OUTLINE Background: FLEDGED project and scope of the work Process description Performance index definition Results 5

6 Process description drying and sorption enhanced gasification (SEG) Oxygen Sorption enhanced gasifier (SEG) separation unit CO 2 to geological storage (not to be used) Combustor Calciner CO 2 purification & M = 2 or M = 3 CO 2 -rich flue gases as received Gasifier Carbonator cooler dryer Reformer () cleaning & Heat recovery steam cycle Steam Regressed from the 200 kw th pilot at Un. Stuttgart Electric power SNG case Sorptionenhanced TREMP methanation - Gas composition: (SES) SNG CO, H2, CO2, H2O WGS equilibrium deviation with T Heat case Drying: tube bundle dried using condensing steam at 6 bar. Moisture from 45 to 20%wt. Gasifier-carbonator: - Steam-to-carbon (molar) = 1.5 CH4 kg CH4 /kg biomass, db constant C2+ (C2H4) decrease Offgas with temperature Ultimate composition [%wt. db] C H 6.08 N 0.20 S 0.02 O Cl 0.05 Ash Solids to Combustor-Calciner: Offgas recovery (cogenerative ICE) Unconverted char min. [Conversion=f(T), % FC] CaCO3 conversion CaO= min. [X=0.75 Xave, Equilib.] Combustor-calciner: - Complete combustion of char and calcination of CaCO3-910ºC with 30%vol. O2 at inlet (from an ASU) 6

7 Process description drying and sorption enhanced gasification (SEG) Oxygen Sorption enhanced gasifier (SEG) Combustor Calciner M = 2 or M = 3 cooler Gasifier Carbonator Reformer () cleaning & SNG case TREMP methanation case Objective: M-module=2 () and 3 (SNG) after the cleaning and Sorptionenhanced (SES) MM mmmmmmmmmmmm = NN HHH NN CCCCC NN CCCC + NN CCCCC separation unit CO 2 to geological storage (not to be used) CO 2 purification & CO 2 -rich flue gases as received dryer Heat recovery steam cycle Steam Electric power SNG Heat Gasifier temperature modified through gas solid circulation (i.e., different amount of CO2 separated Offgas within the SEG) for achieving the target M-module Offgas recovery (cogenerative ICE) 7

8 Process description production plant Oxygen Sorption enhanced gasifier (SEG) M = 2 or M = 3 cooler Reformer () cleaning & case Reformer needed before cleaning and conditioning for reducing CH4 content (dedicated unit for tar removal avoided) separation unit CO 2 to geological storage (not to be used) Combustor Calciner CO 2 purification & CO 2 -rich flue gases as received Gasifier Carbonator dryer Heat recovery steam cycle Steam Electric power Heat Sorptionenhanced (SES) Offgas Offgas recovery (cogenerative ICE) cleaning: - cooling (80ºC) - Water scrubber (40ºC) - H2S removal: liquid redox process (Febased) H2S S and H2O (LO-CAT process) - Compression up to 25 bar - Cooling and water/h2s traps 8

9 Process description production plant Oxygen Sorption enhanced gasifier (SEG) M = 2 or M = 3 cooler Reformer () cleaning & case Combustor Calciner Gasifier Carbonator Sorptionenhanced (SES) Heat Offgas Two sequential reactors: conventional direct + SE- separation unit CO 2 to geological storage (not to be used) CO 2 purification & CO 2 -rich flue gases as received dryer Heat recovery steam cycle Steam Electric power Offgas recovery (cogenerative ICE) Exhaust gas (H2, CO mainly) burnt in an engine (40 %) for additional power production Heat recovery steam cycle (480ºC, 28 bar) 9

10 Process description SNG production plant Oxygen Sorption enhanced gasifier (SEG) Combustor Calciner M = 2 or M = 3 cooler Gasifier Carbonator Reformer () cleaning & SNG case TREMP methanation Reformer not needed cleaning: - Similar to that of the plant but including an OLGA process for tar removal Methanation process: - 3 adiabatic stages, 35 bar and 310/210ºC SNG R1 R2 R3 separation unit CO 2 -rich flue gases Heat R4 CO 2 to geological storage (not to be used) CO 2 purification & as received dryer Heat recovery steam cycle Steam Electric power condensate 10

11 OUTLINE Background: FLEDGED project and scope of the work Process description Performance index definition Results 11

12 Performance index definition Cold Gas Efficiency of the SEG process: CCCCCC SSSSSS = mm ssssssssssss LLLLLL ssssssssssss mm bbbbbb,ssssss iiii LLLLLL bbbbbbbbbbbbbb chemical energy of the syngas chemical energy introduced with the biomass into SEG Global Cold Gas Efficiency: CCCCCC gggggggggggg = mm DDDDDD/SSSSSS LLLLLL DDDDDD/SSSSSS mm bbbbbbbbbbbbbb,aaaa LLLLLL bbbbbbbbbbbbbb,aaaa chemical energy of the final product (/SNG) Equivalent Cold Gas Efficiency: - If P el,net <0 (import electricity) additional fuel consumption CCCCCC eeee = mm DDDDDD/SSSSSS LLLLLL DDDDDD/SSSSSS mm bbbbbbbbbbbbbb LLLLLL bbbbbbbbbbbbbb PP eeee,nnnnnn ηη eeee,rrrrrr Fuel saving associated to the electric power output (34% for a biomass SC) 12

13 OUTLINE Background: FLEDGED project and scope of the work Process description Performance index definition Results 13

14 Performance results SEG- production plant SEG-SNG production plant Gasifier temperature [ºC] input to gasifier [%] input to combustor-calciner [%] CGE SEG [%] CGE global [%] Net electric output [MW e ] (P el,net ) Steam turbine electric output [MW e ] Electric consumption [MW e ] Off gas engine electric output [MW e ] CGE eq [%] Lower gasifier temperature in the SNG plant since more CO2 capture needed (M higher) Larger amount of unconverted char less biomass sent to the calciner CGE SEG turns larger Global CGE larger for the SNG plant (no reformer needed, CGE SEG larger and no off-gas produced) SNG plant needs more electricity import advantage still on CGE eq CO 2 capture ratio [%]

15 Results: Well to Wheel Analysis Primary source Well-to-Tank (Fuel production) MJ P /MJ F g CO2,eq stored/mj F g CO2,eq emitted/mj F Diesel Oil 0, ,1 Gasoline Oil 0, ,0 Conventional CNG Natural gas 0, ,2 Bio-CNG from SEG 0, Conventional bio- 1, Bio- from SEG 1, TtW (fuel use) Well-to-Wheel Similar primary g g energy consumption CO2,eq /MJ CO2,eq g CO2,eq g CO2,eq F with respect emitted/mj to conventional F emitted/km stored/km 73,6 from 89biomass (larger 106 than -- 73,9 fossil fuel production 88 routes) ,3 Possibility of carbon 71 capture ,0 8,1 12, ,3 2,4 2, ,3 5,2 6,3-155 Primary energy expended per MJ of final fuel produced Fossil fuel based value chains are positive emitters, while conventional is almost neutral SEG-based processes have the potential to store gco2/km turns out into a carbon negative mobility (net C removal from the atmosphere) Joint Research Centre-EUCAR-CONCAWE collaboration, WELL-to-WHEELS Report,

16 Concluding remarks A process assessment of two synthetic fuel production plants based on a flexible Sorption Enhanced Gasification process of biomass has been carried out Synthetic Natural Gas production plant yields biomass-to-fuel efficiency of almost 54% (CGE eq ), which is slightly higher than that of the production plant (52%) Based on the WtW analysis: a bio- vehicle emits around 100 gco2/km less than a conventional diesel vehicle, which is the same saving for the conventional CNG vehicle and the bio-cng one Assessed processes allow capturing between 63-67% of inlet C from biomass, which turn into gco2/km removed from the atmosphere and stored ( carbon negative mobility) 16

17 14 th Greenhouse Gas Control Technologies conference, 21 st -25 th October, Melbourne (Australia) Thanks for your attention This project has received funding from the European Union s Horizon 2020 research and innovation Programme under grant agreement No