30th ISTC Japan Workshop on Advanced Catalysis Technologies in Russia

Fluidized bed catalytic pyrolysis and gasification of biomass for production of fuel out of renewable

resources

Prof. Z.R.Ismagilov

Laboratory of Environmental Catalysis, Boreskov Institute of Catalysis SB RAS,

Novosibirsk, Russia, www.catalysis.ru/envicat

BIOMASS YEARLY WORLD GROWTH - UP TO 200*109 t

TO DATE YEARLY BIOMASS CONSUMPTION (FOOD, CONSTRUCTION, FUEL PRODUCTION) - 3-4 %

ADDITIONAL INVOLVING OF 3 % OF BIOMASS FOR FUEL PRODUCTION IS EQUIVALENT TO 3*109 t OF CRUDE OIL REPLACEMENT

Diagram of biomass processing and utilization

Catalytic fluidized bed for biomass pyrolysis and gasification

1. Increase of the process rate and decrease of the temperature to 600-700оС2. Increase of the content of H2 and CO in the products to 10-15 vol.% and regulation of H2/CO ratio 3. Decrease of the yield of liquid and solid products of pyrolysis4. Production of low tar or tar free synthesis gas.

• For the studies semolina was taken as a biomass model object, with the following

chemical composition (wt. %): hydrogen 6.92; carbon 39.18; nitrogen 1.81; ash 1.17.

• The combustion catalyst CuxMg1-xCr2O4/γ-Al2O3 (IC-12-73) was used in the

experiments. The inert bed material used in the setups 2 and 3 was granulated γ-Al2O3.

• All setups were equipped with the system for on-line continuous gas sampling for GC

analysis.

• The goal of this work was to study the processes of biomass pyrolysis and

gasification in experimental facilities containing fluidized bed reactors. Three setups

used in this work were different by the way of conducting the pyrolysis and gasification

processes.

Experimental

Experimental setup 1

In the setup 1 the reactor contains fluidized bed catalyst in lower part for catalytic combustion of fuel. The height of the fluidized bed being 50 cm and biomass was fed directly to the hot fluidized bed at the height of 40 cm.

Experimental setup 2

The setup 2 contains two fluidized bed reactors. Lower reactor is for fuel catalytic combustion and upper reactor loaded by inert bed material (γ-Al2O3). The biomass was fed into the fluidized bed of the upper reactor.

Scheme of experimental setup 1

1,2 – reactor: 1 – lower part with fluidized bed of catalyst; 2 – upper part; 3 - high-temperature cyclone; 4 - low-temperature cyclone; 5 – biomass feeder; 6 - rotameter; 7 - valve; 8 – reservoir with fuel; 9 - multi channel temperature control system; 10 - plunger micro pump for fuel injection; 11 - grid filter and fine filter; 12 - ejector

Characteristics of the setups.

ValueCharacteristicsSetup 1 Setup 2 Setup 3

Dimensions, mm 1800 x 600 x 600 2500х2500х600 4000 x 3000 x 1500Reactor type material diameter, mm

FBstainless steel

50

FBstainless steel

50

FBstainless steel

300Catalyst loading, dm3

fraction, mm

IC-12-720.5

1.6-2.0

IC-12-721.0

1.6-2.0

IC-12-724.0-5.00.4-0.8

Inert bed loading, dm3

fraction, mm

- γ-Al2O30.3

2.0-2.5

γ-Al2O33.0

0.2-0.4Temperature of working zone, oC 650-800 650-800 650-800Air flow, m3/h 2.5 6.0 30Fuel flow, l/h 0.2 0.3 1-1.5Biomass flow, kg/h 0.3 0.5 10

The experimental conditions and results of GC analysis of reaction products. Temperature in the biomass feeding zone – 750oC.Setup 1.

Feed conditions Products, % vol. Fluidized

bed Ejector Fuel

inject TCD FID Fuel,

l/h Semolina, kg/h Air,

m3/h N2,

m3/h N2,

m3/h Air, m3/h

α*

H2 O2 N2 CO CH4 C2H6 C3H8 C4H10 iso-C4H10

C5H12

experiments with variation of air flow (in fluidized bed) 0.1 0.3 1.5 0 0.375 0.175 0.87 0.2 11.3 78.4 0.01 0.03 0.01 0.01 0.01 0 0 0.1 0.3 1.4 0 0.375 0.175 0.83 1.2 8.9 77.6 0.6 0.1 0.08 0.09 0.06 0.01 0.02 0.1 0.3 1.3 0 0.375 0.175 0.79 2.7 6.3 78.1 1.8 0.6 0.4 0.5 0.4 0.06 0.09 0.1 0.3 1.1 0 0.375 0.175 0.71 4.1 3.2 79.9 4.3 1.2 0.8 0.9 0.7 0.3 0.3 0.1 0.3 0.9 0 0.375 0.175 0.63 5.2 1.0 77.8 6.3 1.8 1.2 1.3 0.8 0.7 0.6

experiments at fixed air flow (checking stability of the process) 0.1 0.3 1.0 0 0.375 0.175 0.67 4.6 2.8 78.2 5.1 1.3 0.9 1.0 0.8 0.5 0.4 0.1 0.3 1.0 0 0.375 0.175 0.67 4.4 2.7 78.1 4.9 1.2 1.0 0.9 0.8 0.4 0.3 0.1 0.3 1.0 0 0.375 0.175 0.67 4.0 2.9 77.9 5.2 1.1 0.8 0.9 0.7 0.5 0.3 0.1 0.3 1.0 0 0.375 0.175 0.67 3.9 3.0 77.9 4.7 1.3 0.8 0.9 0.7 0.4 0.4 0.1 0.3 1.0 0 0.375 0.175 0.67 4.3 2.7 78.0 5.0 1.3 0.8 0.8 0.7 0.4 0.4

experiments with variation of air flow (at fixed total gas flow in fluidized bed) 0.1 0.3 0.6 1.6 0.375 0.175 0.51 5.6 0.5 78.2 7.2 2.1 1.5 1.4 0.7 0.3 0.2 0.1 0.3 0.9 1.3 0.375 0.175 0.63 5.0 0.9 77.5 6.5 1.6 1.3 1.1 0.5 0.3 0.15 0.1 0.3 1.1 1.1 0.375 0.175 0.71 4.5 2.9 77.3 5.1 1.3 0.9 0.07 0.2 0.1 0.1 0.1 0.3 1.4 0.8 0.375 0.175 0.83 2.3 7.8 78.4 1.5 0.4 0.05 0.4 0.02 0.01 0.01 0.1 0.3 1.7 0.5 0.375 0.175 0.95 0.3 8.8 78.5 0.1 0.01 0.01 0.01 0 0 0

*α is oxygen to fuel equivalence ratio, i.e. the ratio of the actual amount of supplied oxygen to that of oxygen required for complete combustion of biomass and fuel

Experimental setup 2

The setup 2 contains two fluidized bed reactors. Lower reactor is for fuel catalytic combustion and upper reactor loaded by inert bed material (γ-Al2O3). The biomass was fed into the fluidized bed of the upper reactor.

Pyrolysis and gasification of semolina in fluidized beds with different materials. Setup 2.

Gases contentNo.О2,

% vol.Н2,

% vol.СО,

% vol.СН4,

% vol.NOx,

mg/m3Примечание

Fuel (without semolina) 850-900oC1 2.6 - 0.51 - 412 2.7 - 0.50 - 32

Experiment 1; fuel – 300 ml/h, semolina - 1000 g/h, quartz – 300 ml, 700oC6 0.1 1.53 10.12 0.35 9617 0.0 1.48 9.98 0.35 10848 0.0 1.33 10.12 0.35 1043

Н2 - 1.44%СО – 10.02%СН4 – 0.35%

Experiment 2; fuel – 300 ml/h, semolina - 1000 g/h, quartz – 300 ml + catalyst – 100 ml, 700oC11 0.0 5.84 10.64 0.89 89012 0.0 5.84 10.63 0.98 97413 0.0 5.84 10.46 0.88 986

Н2 - 5.84%СО – 10.54%СН4 – 0.92%

Experiment 3; fuel – 300 ml/h, semolina - 950 g/h, Al2O3 – 300 ml, 750oC11 0.0 4.8 5.96 0.71 186512 0.0 4.6 5.87 0.73 183813 0.0 4.7 5.64 0.71 1874

Н2 - 4.7%СО - 5.79%СН4 - 0.72%

Conversion of biomass upon the variation of specific biomass flow. Setup 3.

Dependencies of the content of gaseous products of air conversion of biomass and initial gases on the value of specific biomass flow.Height of the stationary bed - 0.32 m, height of fluidized bed - 0.5 m, loading of γ-Al2O3 (d=1mm) - 2.5 dm3, T = 720-780oC, residence time - 0.45 c.

Conversion of biomass upon the variation of contact time with reaction medium. Setup 3.

Dependencies of the content of gaseous products of air conversion of biomass and initial gases on the biomass contact time with reaction medium. Light dots – inert packing γ-Al2O3; dark dots – catalyst IC-12-72. Height of fluidized bed - 0-0.5 m, loading of γ-Al2O3 (d=1mm) - 0-2.4 dm3, T = 670-700oC, biomass flow - 5.8-7.2 kg/h, specific biomass flow - 0.71-0.88 kg/m3.

Conversion of biomass upon the variation of additional steam flow Setup 3.

No. of experiment Steam-air conversion Pyrolysis

No.

Parameters Meas. units

1 2 3 4 Technological parameters of the process

1 Air flow m3/h 8.2 8.2 8.2 - 2 Nitrogen flow m3/h - - - 8.2 3 Biomass flow kg/h 6.7 6.7 4.1 8.3 4 Specific biomass flow kg/m3 0.8 0.8 0.5 1.0 5 Water flow kg/h 0.5 1.1 1.8 0 6 Specific water flow kg/m3 0.06 0.13 0.22 0 7 Water flow/biomass flow g/kg 75 160 435 0 8 Initial bed temperature oC 615 630 625 620 9 Operating bed temperature oC 705 700 710 570

10 Temperature in CHG oC 660 670 670 650 Composition of the steam-air conversion and pyrolysis products

1 H2 vol.% 9.0 9.0 5.5 0 2 O2/Ar vol.% 4.0 3.0 4.9 2.8 3 N2 vol.% 57.2 52.0 62.3 72.8 4 CH4 vol.% 1.5 2.0 0.9 0.9 5 CO vol.% 12.4 15.0 7.4 7.0 6 CO2 vol.% 9.4 13.0 10.0 3.5 7 C2H4 vol.% 1.0 1.0 0.5 0.4 8 C2H6 vol.% 0.1 0.l 0 0.1 9 H2O vol.% 2.0 2.0 2.0 2.0 Balance vol.% 96.8 97.1 93.5 89.5

Technological characteristics of the process of steam-air biomass conversion upon the variation of additional steam flow (experiments 1-3) and of the biomass pyrolysis process (experiment 4).

Results of the GC/MS analysis of liquid fraction of the biomass pyrolysis and gasification products. Setup 1.

Conclusions:

1. Main products of biomass conversion are the gases: H2, CO and CH4 . The maximum quantaties of these products are: H2 - 8-11% vol., CO - 18-20%vol., CH4 - 2-2.5%vol.

2. Conducting pyrolysis in the inert atmosphere, or conversion with the addition of water vapor into the reaction zone do not have any advantages over the conventional catalytic process

3. At the values of oxygen excess ratio α>0.60-0.65 the process proceeds withpreferential formation of the gaseous conversion products, while at the values α<0.60the evolving of liquid and solid products is also noticeable; at α<0.50 the evolving ofliquid and solid products becomes very abundant, while that of the gaseous products,on the contrary, decreases. Most optimal is to conduct the process at α~0.5-0.65. In thiscase, the values of the yields of gaseous products of biomass pyrolysis and gasificationare maximal, and evolving of liquid and solid products is minimal.