Giovanna Ruoppolo Istituto di Ricerche sulla Combustione_CNR. Giovanna Ruoppolo IEA task 14 May, Ischia

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1 Giovanna Ruoppolo Istituto di Ricerche sulla Combustione_CNR Giovanna Ruoppolo IEA task 14 May, Ischia

2 Gasification of biomass Tar abatement with in bed catalyst Reducing of segregation phenomena Co-gasification Co-gasification of biomass and coal Co-gasification of biomass and waste Giovanna Ruoppolo IEA task 14 May, Ischia 2

3 Air, Steam, CO 2, and/or O 2 FUEL CO, H 2, CO 2, H 2 O, CH 4, C 2 H 4 + unconverted tars (all organic compound with mass > C 6 H 6 ) The main challenges of biomass gasification are: Good control of temperature in the reactor High heating rate (hundreds of degrees per second) and high temperatures (around 8 C) are necessary to maximize the gas yield TARS conversion TARs condense in the cold parts plugging of tubes or agglomeration phenomena TARS removal by filtration lost of efficiency since they still contain energy Giovanna Ruoppolo IEA task 14 May, Ischia 3

4 Fluidized bed technology Bubbling fluidized bed Circulating fluidized bed Cyclone : Bed hot particles : Biomass and char : grid Advantages: uniform temperatures and high heating rates, greater tolerance to particle size range Drawbacks: low density biomass fuel (with respect to the bed particles) segregates to the surface of the bed reducing the conversion rate. Fine carbon particles produced in the reaction process elutriate (increasing the solid load to the cyclone and the filter). Fused ash and tar condensation provokes defluidization. Giovanna Ruoppolo IEA task 14 May, Ischia 4

5 Cleaned gasification gas contains mostly gas phase (light hydrocarbons + H 2, CO 2, CO, H 2 O) 1) Fuel feeder system 2) Tars and gasification products The catalytic tars conversion can both decrease tar production and modify gas composition. 1: Primary method: the catalyst is mixed with biomass directly inside the gasifier. Single-stage process 2: Secondary method: the catalyst is placed down stream the gasifier. Dual-stage process Gasifying gas (air, O 2, H 2 O) Using a fluidized bed reactor it is possible to realize a single stage process using the catalyst directly inside the reactor and coupling good control of temperature and high heating rate of the biomass fuel. Giovanna Ruoppolo IEA task 14 May, Ischia 5

6 The fluidized bed gasifier consists of two vertical stainless steel tubes connected by a conical adapter, the lower tube has an Internal Diameter (ID) of 14 mm and is 11 mm in height, and the upper tube has an ID of mm and is 18 mm in height. Giovanna Ruoppolo IEA task 14 May, Ischia 6

7 CO2 CO CH4 H Cyclone Ø mm Flare Filter Filter FB gasifier isokinetic solid sampling P 1 l/h Analyzer (CO2, CO, H2, CH4) Biomass feeder Tar sampling Ø 14 mm P Tar condensers Heated part Mass flow controller N2 Mass flow controller Air Preheater Steam generator P Water Balance Gas Online analysis for CO, H 2, CO 2 CH 4 Offline micro GC analysis for lighter hydrocarbon (nc2-nc7) CO2, CO, Ch4 and H2 concetration (%) quarzite 18/9/8 Time (min) Analysis Solid Gravimetric analysis Granulometric analis LECO CHN analysis cumulative distribution, % diameter, m frequency function, % Tar Gravimetric analysis for condensed species ( C and -1 C) Giovanna Ruoppolo IEA task 14 May, Ischia 7

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9 Biomass characteristics: commercial pellet Moisture (%wt) Volatiles (wt%) Fixed carbon Ash (wt%) C (%wt H (%wt) O (%wt) LHV (wet fuel) (wt%) ) MJ kg -1 Bed material characteristics: Haider and Levenspiel, Powder Techn., (1989) 58, p.63, Eq. 21 Geldart "Gas Fluidizat. Techn.", 1986 J. Wiley & Son - eq 2.27 (dp>1 mm) Material Density (kg/m 3 ) Amount loaded (kg) Size ( m) u mf (m/s) u t (m/s) quarzite olivine calcined dolomite catalyst (wt%)ni on -Al 2 O 3 (Sasol) with high mechanical resistence (Ka=,1) prepared by wet impregnation starting from nickel nitrate and calcined at 85 C. Surface area =156m 2 /g. Active phase nickel aluminate Giovanna Ruoppolo IEA task 14 May, Ischia 9

10 Experimental conditions Q air = 2.25 Nm 3 Q N2 =.6 Nm 3 Q fuel =2.9 kg/h (dry) Q H2O =1.6 kg/h T= 78 C =.17 S/B=.65 u =.3 m/s H/D=1.5-2 The gas concentration rapidly reached a stable value and no significant deviations were observed for the entire duration of the test. 4 dry gas concentration (%) 3 1 CO 2 CO H 2 CH 4 C 2 H 4 Quarzite (I) Quarzite (II) Olivine Dolomite Catalyst (I) Catalyst (II) Giovanna Ruoppolo IEA task 14 May, Ischia 1

11 CO 2, CO, H 2 and CH 4 dry concentration, % S /F = S /F =.6 5 S /F =.9 1 S /F = S /F =.6 5 S /F = CO 2 CO Catalyst; ER.3 H 2 Q uartzite; E R =.3 CH 4 S /F = C atalyst; E R =.17 Q uartzite; E R = S /F = S /F =.6 5 Giovanna Ruoppolo IEA task 14 May, Ischia 11 CO 2, CO, H 2 and CH 4 dry concentration, % CO 2, CO, H 2 and CH 4 dry concentration, % CO 2, CO, H 2 and CH 4 dry concentration, % ER=.3; S/F= ER=.3; S/F=.65 ER=.3; S/F=.91 ER=.17; S/F= quartzite catalyst Tar concentration at the exit of gasifier, g/nm 3

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13 Concentrazione di CO 2, CO, H 2 e CH 4, % Air flow Central jet CO 2 CO H 2 CH J, % Giovanna Ruoppolo IEA task 14 May, Ischia 13

14 6 TAR concentration, g/nm Catalyst Quarzite J, % Giovanna Ruoppolo IEA task 14 May, Ischia 14

15 Catalyst Quarzite J, % Giovanna Ruoppolo IEA task 14 May, Ischia 15 Carbon elutriation rate Ec (g/h) Elutriation rate E (g/h)

16 option for overcoming the limitation of the low energetic density of biomasses since coal has almost double energetic density and the temporarily lacking of biomass availability due to its seasonality Giovanna Ruoppolo IEA task 14 May, Ischia 16

17 + Pelletization of the raw material has shown positive effects in terms of homogenization of the original material Pelletization can improve the raw fuel mechanical properties and, in turn, the carbon conversion efficiency during fluidized bed conversion Fuel Wood pellet GBC /wood pellet (3% w/w) Dim. pellet (D x L), mm 6x 6x Umidità, % w/w 8,5 9,4 Volatili, % w/w 74,1 66,7 C Fisso, % w/w 17,1 22,8 Ceneri, % w/w,3 1,1 C, % w/w dry basis 49,3 55,1 H, % w/w dry basis 5,9 5,7 N, % w/w dry basis <.1,1 O, % w/w dry basis 44,4 38 LHV, MJ/kg 18,5 21,7 Giovanna Ruoppolo IEA task 14 May, Ischia 17

18 8 C 8 C Cat. 85 C 85 C Dol. Qua. U =.35 m/s, Φ =.17, Ψ =.64. Giovanna Ruoppolo IEA task 14 May, Ischia 18

19 The gasification of wood/coal pellets gives rise to a substantially higher elutriation rate of fine particles with respect to wood pellets, as a consequence of the larger ash and fixed carbon content in the wood/coal pellets as well as the lower char reactivity Giovanna Ruoppolo IEA task 14 May, Ischia 19

20 The possibility of producing a syngas from residual materials prone for conversion into methanol was analyzed Giovanna Ruoppolo IEA task 14 May, Ischia

21 Fuel: Biomass (75wt%): Dry olive husk produced in substantial amounts in the Campania region (75wt%) Waste (25wt%): Polyethylene Terephthalate (PET) from packaging of drink bottles and Tyre granules, obtained by proper demolition of automobile. Bed material: FUELS OH OHPET OHTYRE -Alumina prevents the agglomeration phenomena associated with the use of olive husk Mixed Al and Ni/γ- Al2O3 (6%wt). Non different performances with the 1%wt catalyst Pellets dimensions (diameter x length), mm 6 x 6 x 6 x Moisture, wt.% 8, Volatiles, wt.% 68, Fixed carbon, wt.% 19, Ash, wt.% 3, Carbon, wt.% on dry basis 55, Hydrogen, wt.% on dry basis 5, Nitrogen, wt.% on dry basis Oxygen, wt.% on dry basis 37, Low heating value, MJ/kg 19, Giovanna Ruoppolo IEA task 14 May, Ischia 21

22 Temperature range:75-85 C S/F range:.6-1 ER=.1 Unexpanded Bed height:.18m OHPET and the Ni base catalyst at 827 C ER=.1 and S/F=1. % vol, dry base Time (min) 1 A stable state observed for the all time suggests that whatever are the adopted experimental conditions: No problems in the fuel feedstock handling and metering devices. agglomeration problems do not occur catalyst deactivation does not occur H 2 CO CO 2 CH Temperature C Giovanna Ruoppolo IEA task 14 May, Ischia 22

23 CO 2 ; CO, CH 4 and H 2 dry composition, vol% CO2 CH4 CO H2 C2H4+C2H6 T=752 C S/F=.8 Al T=745 C S/F=.6 T=748 C S/F=1. OHPET T=845 C S/F=.6 T=827 C S/F=1. T=782 C S/F=.5 OH CO 2, CO, CH 4 and H 2 dry composition, vol% CO2 CH4 CO H2 T=75 C S/F=1. T=839 C S/F= OHTYRE T=848 C S/F=1. The presence of PET and TYRE strongly enhances the H 2 production Giovanna Ruoppolo IEA task 14 May, Ischia 23

24 H 2 /CO ratio, T=752 C S/F=.8 Al T=745 C S/F=.6 T=748 C S/F=1. T=845 C S/F=.6 T=827 C S/F=1. T=782 C S/F=.5 T=75 C S/F=1. T=839 C S/F=.7 T=848 C S/F=1. The H 2 /CO ratio is always higher than that obtained with the olive husk pellet confirming that the co-gasification is a suitable strategy to produce a syngas with the H 2 /CO required for the methanol synthesis 1 H 2 /(CO+CO 2 ) and CO 2 /CO ratio, OHPET H2/CO+CO2 CO2/CO T=752 C T=745 C S/F=.8 S/F=.6 Al T=748 C S/F=1. OHPET T=845 C S/F=.6 T=827 C S/F=1. OH T=782 C S/F=.5 OH T=75 C S/F=1. OHTYRE T=839 C S/F=.7 OHTYRE T=748 C S/F=1. The yield of methanol is sensitive to the H 2 /(CO + CO 2 ) ratio, while the selectivity to the CO 2 /CO ratio When the CO 2 /CO ratio is >1, the selectivity of methanol decreases sharply WithapartialremovalofCO 2 can be changed greatly the CO 2 /CO in the feed gas Giovanna Ruoppolo IEA task 14 May, Ischia 24

25 Tar concentration at the exit of gasifier, g/nm T=752 C S/F=.8 Al T=745 C S/F=.6 T=748 C S/F=1. T=827 C S/F=1. T=845 C S/F=.6 T=75 C S/F=1. T=848 C S/F=1. T=839 C S/F=.7 T=782 C S/F=.5 OHPET OHTYRE OH The level of tar decreases as the temperature increases. The presence of catalyst reduces the amount of tar. The tar decrease is reflected in an higher formation of light hydrocarbons C 2 H 6 and C 2 H 4. Giovanna Ruoppolo IEA task 14 May, Ischia 25

26 Entrained carbon, g/nm OHPET OHTYRE OH entrained char The temperature increase reduces the carbon elutriated The OHPET pellets show a lower carbon elutriation rate probably due to the higher reactivity of the fuel component Giovanna Ruoppolo IEA task 14 May, Ischia 26

27 The presence of a catalytic bed, especially in the case when an ad hoc reactor configuration is used: adoption of a central jet in addition to the conical distributor, increases hydrogen rich syngas yield and decreases tar production. However some expected negative effects of such configuration on attrition phenomena has been highlighted. The effect of equivalent ratio and the presence of steam affect the performance of gasifier less than the presence of catalyst provided that the segregation phenomena are negligible. The use of pellets results into beneficial effects on solid particles emissions but when mixed pellets are used there is an important role played by properties of the parent fuels Among the mixed pellet tested, the biomass/plastic pellets exhibited promising results in terms of the hydrogen yield even if they suffered from a higher production of TAR Giovanna Ruoppolo IEA task 14 May, Ischia 27

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29 Paola Brachi, Riccardo Chirone, Francesco Miccio, Michele Miccio, Antonio Picarelli, Giovanna Ruoppolo (14) Fluidized bed cogasification of biomass and polymeric wastes for a flexible end-use of the syngas: Focus on bio-methanol in Fuel Giovanna Ruoppolo, Francesco Miccio, Paola Brachi, Antonio Picarelli, Riccardo Chirone (13) Fluidized Bed Gasification of Biomass and Biomass/Coal Pellets in Oxygen and Steam Atmosphere in Chemical Engineering transactions G. Ruoppolo, P. Ammendola, R. Chirone, F. Miccio (12) H2-rich syngas production by fluidized bed gasification of biomass and plastic fuel in Waste management Ruoppolo, G; Miccio, F; Chirone, R (1) Fluidized Bed Cogasification of Wood and Coal Adopting Primary Catalytic Method for Tar Abatement in Energy & fuels Giovanna Ruoppolo IEA task 14 May, Ischia 29