fluidized bed oxyfuel combustion activities in circe 2nd ... · 2nd international workshop on...

Fluidized bed oxyfuel combustion activities in CIRCE

2nd International Workshop on Oxyfuel FBC TechnologyJune 28-29th 2012-StuttgartIsabel Guedea, Irene Bolea, Carlos LupiáñezYolanda Lara, Pilar Lisbona , Ana Martínez

Luis I. Díez, Luis M. Romeo

Edificio CIRCE / Campus Río Ebro / Mariano Esquillor Gómez, 15 / 50018 ZARAGOZA

Tfno. (+34) 976 761 863 / Fax (+34) 976 732 078 / web: www.fcirce.es / email: [email protected]

,

Contents

1. What is CIRCE

2. CO2 capture laboratories and team

3. Recent results: CO emissions

o TGA experiments

O BFB i to Oxy-BFB experiments• Air- O2/CO2- O2/RGF• Secondary gas

4. Conclusions

1. What is CIRCE?

Knowing how, teaching how

Research TrainingUIP

g

TransferTransfer

T h l ServicesTechnology

Location

Permanent Delegation in Brussels

Zaragoza Headquartersq

1. What is CIRCE?

1. What is CIRCE?Thermal division

CIRCE

o Non-profit private organization, sponsored by the University of Zaragoza, the Government of Aragón and Spanish Industries

o R&D: focus on efficiency and renewable energy

o Thermal division (25 people):o Thermal division (25 people):

• Biomass pre-treatment (drying and milling), CFD simulation, co-firing PF pilot plant (500 kW )firing PF pilot plant (500 kWt)

• Plastic and biomass gasification lab-scale plant(5 kWt)

• CO2 capture: oxy- BFB laboratory; solid looping systems based on CFB; reduction of energy penalties in CO2 capture systems

1. What is CIRCE?

Thermal Division Laboratories

f Co firingGasification Co-firing

1. What is CIRCE?

Thermal Division Laboratories

CO t il t l tOxy-BFB

CO2 capture pilot plants

CDual-CFB

1. What is CIRCE?

Contents

1. What is CIRCE



o TGA experiments


4. Conclusions

Dual-CFB

OBJECTIVE

o Hydrodynamic characterization of two interconnected of two interconnected circulating fluidized bed

• Hydrodynamic modeling

• Scale up of the results

Lisbona et al. (2011) Applied Energy• Martínez et al.(2009). TCCS-5, Trondheim• Romeo et al. (2010). GHGT-10, Amsterdam

M tí t l (2012) 21 FBC N l


• Martínez et al. (2012). 21-FBC, Naples

The Team

o PhD. Luis Miguel Romeoo g

o Yolanda Lara, Ana Martínez, Pilar LisbonaNew design Supercritical Steam Cycle

• Optimization of the calcium looping process

• Heat integration in a supercritical steam cycle

Capture Cycle + Compression Train

• Waste coal valorization with calcium cycle

• Different sorbents testing

Original power plant

• Integration with cement plants

• Romeo et al (2009) Chemical Engineering Journal• Romeo et al. (2009) Chemical Engineering Journal• Romeo et al. (2009) Fuel Processing Technology• Lisbona et al. (2010) Energy and Fuels• Romeo et al. (2011) Greenhouse Gases Science and TechnologyRomeo et al. (2011) Greenhouse Gases Science and Technology• Martínez et al. (2012) International Journal of Greenhouse Gas Control


Oxy-BFB

OBJECTIVE

o Technical feasibility study of Oxy-co-firing: O2/CO2 for coal and biomass combustion in fluidized bed

• Romeo et al. (2009) 1st Oxyfuel Combustion Conference, Cottbus• Guedea et al. (2010), 10th GHGT, Amsterdam• Lupiañez et al (2011) 5th CCT Zaragoza


Lupiañez et al. (2011), 5 CCT, Zaragoza• Bolea et al. (2012), 21th FBC, Napoles

The team

o PhD Luis Ignacio Díez and PhD Luis Miguel Romeo o PhD. Luis Ignacio Díez and PhD. Luis Miguel Romeo

o Irene Bolea, Carlos Lupiáñez, Isabel Guedea

Romeo et al. (2011) Experimental Thermal and Fluid Science

• CO2 capture integration in coal-fired plants

• Heat transfer under OF conditionsLupiáñez et al. (2011) Fuel Processing Technolog

• Desulphurization under OF conditions

• NOx emissions under OF conditions

Technology

Lupiáñez et al. ( b it d) F l

• Hydrodynamic and combustion modeling

• Large oxy-CFB simulation Guedea et al. (2011)

(submmited) Fuel Processing Technology

• Large oxy-CFB simulation ( )Chemical Engineering Journal

Bolea et al. (2012) ( )Applied Energy


Projects

CIRCE Spanish GovernmentCIRCE p

Spanish R&D plan

ENE2005 03286 (2005 2008)ENE2005-03286 (2005-2008)CIT440000-2009-26 (2009)ENE2009-08246 (2009-2011)

Oxy-BFBCIUDENCIUDEN

(since 2009)

O2GEN

FP7FP7


Facility

Test facility descriptiono 90 kWt O2/CO2 bubbling fluidized bed

2. CO2 capture laboratorios and team

Facility

o Great flexibility of oxy-BFB: Different fuels: anthracite, bituminous, lignite, biomass, coke [O2] 20-60% Secondary gas: 0-10-20%y g Fluidization gas:

• Air,Air,• O2/CO2 from canisters • O /RFG (Recycling ratio from 0-70%)• O2/RFG (Recycling ratio from 0-70%)

2. CO2 capture laboratorios and team


FacilityFacility

PLANT CONTROL

y

18 Thermocouples (14 gas circuit, 4 water circuit)

11 Pressure sensors (9 gas circuit, 1 water circuit, 1 compressed air)

3 Pitot tubes (gas circuit), 4 turbine flowmeters (water circuit)

Gas analyzer: CO, CO2, NO, SO2 (NDIR), O2 (paramagnetic)

1 Moisture sensor 1 Moisture sensor

Two manually ash samples in FB

Two manually ahs samples in the cyclone and fall chamber

Two secondary gas injection (0.5 and 0.8 m)


Contents

1. What is CIRCE



o TGA experiments


4. Conclusions


The rate of coal combustion in oxyfuel conditions is a key point in the design and modeling of boilers

New oxidizing atmosphere:o High CO2 concentration enhances char gasification: C+CO2=> COo Boundary layer oxidation of CO in FBC with large particle it may become

influential affecting the mass transfer of O2 to the particle surface2

o High O2 concentration promotes higher burning rate and particle temperature

o O has a lower diffusivity in CO than in No O2 has a lower diffusivity in CO2 than in N2

o Modifications in the micro structure of coal and in reactive surface area under O2/CO2 atmospheres

o Higher specific heat of CO2 in comparison to N2: lower gas and particle temperature

Further research3. Recent Results: CO emissions

Contents

1. What is CIRCE



o TGA experiments


4. Conclusions

TGA experiments : conditions

o Reactivity changes under O /N and O /CO are expected:o Reactivity changes under O2/N2 and O2/CO2 are expected:

Higher O2 concentration: reactivity

Higher CO2 concentration: reactivity

Depending on the fuel nature different reactivity has been o Depending on the fuel nature, different reactivity has been

observed in TGA oven under OF:

In collaboration with Chalmers University of Technology

Conditions: 850ºC 5 ml/min dp ~ 2 mm Conditions: 850 C, 5 ml/min, dp 2 mm

3. Recent Results: CO emissions

Contents

1. What is CIRCE



o TGA experiments


4. Conclusions

Oxy-BFB experiments: conditions

o Experiments conditions:p Anthracite, bituminous, lignite [O2]: 25,30 and 50 % Fluidization velocity:

• Lower velocities for OF tests: higher O2 at the inlet stream

E f λ 1 2 Excess of oxygen: λ ~ 1.2 Bed temperature

• Higher bed temperatures are obtained under O /CO : higher • Higher bed temperatures are obtained under O2/CO2: higher thermal power

Freeboard temperature is low Efficiency combustion

• Higher efficiency combustion for oxy-firing tests


Oxy-BFB experiments: results

Air -O2/CO2 - O2/RFG

9000.40%850ºC

2COCOCOCR COC

700

800

0 25%

0.30%

0.35%

e (º

C)

CO

)

Proposed by Czakiert et al. (2010)

2

500

600

0.15%

0.20%

0.25%

empe

ratu

re

CO

/(C

O2+

C

Bed Temperature

300

400

0.00%

0.05%

0.10% TeC

Freeboard Temperature

30/70 O2/CO2

30/70O2/RFG

Air

Anthrachite



Air -O2/CO2 - O2/RFG

9000.40% 9000.40%

700

800

0 25%

0.30%

0.35%

e (º

C)

CO

)

700

800

0 25%

0.30%

0.35%

(ºC

)

O)

500

600

0.15%

0.20%

0.25%

empe

ratu

re

CO

/(C

O2+

C

500

600

7

0.15%

0.20%

0.25%

mpe

ratu

re

O/(

CO

2+C

O300

400

0.00%

0.05%

0.10% TeC

300

400

500

0.00%

0.05%

0.10% Tem

CO

Air 30/70 O2/CO2

30/70 O2/RFG

3000.00%Air 30/70

O2/CO2

30/70 O2/RFG

Bituminous


Lignite


CO i i d i hi h th d O /CO o CO emissions under air are higher than under O2/CO2: • Lower temperature

Higher velocity• Higher velocityo CO emissions under O2/RFG are higher than O2/CO2:

• CO is recirculated• CO is recirculated• A new reaction C+H2O CO+H2

o Great difference in lignite CO ratios between air and O /COo Great difference in lignite CO ratios between air and O2/CO2atmosphere• Diffusion control conversion• Particle temperature could be lower than with high rank

coals, gasification reactions are not promoted.



Secondary gas

9000.80%

)

700

8000.60%

ure

(ºC

)

2+C

O)

500

600

0.20%

0.40%

mpe

ratu

O/(

CO

2

300

400

0.00%

TemC

Air AirSG:20%

AirSG:10%

Anthrachite3. Recent Results: CO emissions


Secondary gas

900

10000.80%

)

700

8000.60%

ure

(ºC

2+C

O)

500

600

7000.40%

mpe

ratu

O/(

CO

2

400

5000.20% Tem

CO

3000.00%

30/70SG:10%

30/70 30/70SG:20%

50/50 50/50SG:10%

50/50SG:20%SG:10% SG:20% SG:10% SG:20%


Anthrachite


Secondary gas Secondary gas

9000.80%

700

8000.60%

re (º

C)

+C

O)

500

6000.40%

mpe

ratu

/(C

O2+

300

400

500

0 00%

0.20%

Tem

CO

/

3000.00%

Air AirSG:10%

AirSG:20%

Lignite3. Recent Results: CO emissions


SECONDARY GAS - O2/CO2

9000.80%

SECONDARY GAS O2/CO2

700

8000.60%

e (º

C)

+C

O)

500

6000.40%

pera

tur

/(C

O2+

400

5000.20%

Tem

p

CO

/

3000.00%

50/50 50/50SG:10%

50/50SG:20%

25/75 25/75SG:10%

25/75SG:20% SG:10% SG:20%SG:10% SG:20%

3. Recent Results: CO emissionsLignite


Higher [O2] at the inlet reduces CO formationg [ 2] Secondary gas does not have always a positive influence Higher CO formation with anthraciteHigher CO formation with anthracite Higher CO formation with lower temperatures CO is going to be crucial in the NO emissions CO is going to be crucial in the NOx emissions

230600Lignite-25/75 O2/CO2

NO

190

210

300

400

500

x( p

pm)

(ppm

)

NOx

150

170

100

200

300

NO

x

CO

(

CO


1500 1700 1900 2100 2300t (s)

Contents

1. What is CIRCE



o TGA experiments


4. Conclusions

4. Conclusions

1 Further research and modeling on CO formation and char conversion1. Further research and modeling on CO formation and char conversionunder oxy-firing conditions is needed

2 Higher temperature involves lower ratio CO/CO although also the2. Higher temperature involves lower ratio CO/CO2, although also the

gasification's reactions can become important. This importance would be

d i b h f ldeterminate by the fuel nature

3. Optimum secondary gas ratio depends on fuel and O2 (%) at the inlet and

fuel nature

4 RFG increases CO concentration since it is accumulated and a new reaction is4. RFG increases CO concentration since it is accumulated and a new reaction is

presented (H2O)

4. Conclusions

T H A N K YO U V E RY M U C H F O R YO U R AT T E N T I O N

Tel . : [+34] 976 761 863 · c [email protected]

ISABEL GUEDEA [email protected] LARA [email protected]

fluidized bed oxyfuel combustion activities in circe 2nd ... · 2nd international workshop on...

Documents