Center of research on energy resources & consumption Test Facility for the Hydrodynamic Characterization of two CFB for Ca Looping Systems Luis M Romeo.

Center of research on energy resources & consumption

Test Facility for the Hydrodynamic Characterization of two CFB for Ca Looping Systems

Luis M Romeo ([email protected])

Pilar Lisbona, Ana Martínez, Yolanda Lara

CIRCE - Center of research on energy

resources & consumption

4th International Workshop on In-Situ CO2 Removal,

Imperial College (London), July 2008


INDEXCIRCE description

Ca looping cycles

Introduction

Objectives

Test facility description

Test plan

Energy integration of Ca looping systems

Objectives

Results


CIRCE description

• non-profit private organisation, sponsored by

R&D in energy and thermal and electrical engineering

experience in coal & biomass combustion, plant tests & monitoring, laboratory work, simulation, CFD, conventional (PF) and advanced (FBC, IGCC, co-firing) concepts, CO2 capture

Utility Mining Educational Government


Experience in EC projects:CFB800: Utility Scale CFB for Competitive Coal Power (RFCS 2004, project RFCR-CT-2005-00009)

VISCON: Visual sensing for optimised control of tube bank performance and enhanced lifetime (5th FP, project NNE5-1999-00463)

INTCON: Intelligent process control system for biomass fuelled industrial power plants (5th FP, project ENK6-2001-00542)

BIOMAX: Maximum biomass use and efficiency in large-scale cofiring (5th FP, project NNE5-2001-00291)

CARNO: Development of a carbon-in-ash notification system. (ECSC 2001, project 7220-PR-130)

BIOCARD: Global process to improve Cynara cardunculus exploitation for energy applications (6th FP STREP, project SUSTDEV 1.2.5 019829)

CLEAN SELECTIVE: Intelligent monitoring and selective cleaning control of deposits in pulverised coal boilers (RFCS 2005, project RFCR-CT-2006-000098)

Experience in CO2 projects (National programs):

Efficiency improvement and reduction of greenhouse gases in existing power stations (2004)

Technical, economical and legal feasibility of technologies for reduction of CO2 emissions from coal (2004-07)

Biomass oxy-co-firing in fluidized bed (2005-08)

CENIT CO2- Spanish national council for RTD in CO2 capture and storage (2006-09)


CIRCE description. Experience in CO2 issues:

Laboratories:

Biomass/coal combustion

Oxyfuel combustion

CFB looping

European Technology Platform for Zero Emission Fossil Fuel Power Plants.

CO2 Spanish Platform. Secretariat (2007)


INDEXCIRCE description

Ca looping cycles

Introduction

Objectives


Test plan


Objectives

Results


Ca looping systems. Introduction

Carbonate looping requires the movement of solids between two different reactors:

CFB for sorbent carbonation and CO2 reaction

CFB for sorbent regeneration and CO2

releasing

Key factor: sorbent stability after high number of cycles

To overcome the loss of sorbent activity two strategies are proposed

operating at high purge,

operating at high solid internal circulations.

Carbonator Calciner

CaO + CaCO3 + CaSO4 + ash

CaO + CaSO4 + ash

CO2

O2

CaCO3

Combustor

Air

Fuel

Fgas + FCO2(1-ηcapt)

Purge (I)

ycomb

1-ycomb

Fgas + FCO2

Purge (II)

Carbonator Calciner

CaO + CaCO3 + CaSO4 + ash

CaO + CaSO4 + ash

CO2

O2

CaCO3

Combustor

Air

Fuel

Fgas + FCO2(1-ηcapt)

Purge (I)

ycomb

1-ycomb

Fgas + FCO2

Purge (II)


Ca looping systems. Introduction

Operation conditions will be defined by a compromise among:

purge percentage

Increment of cost of fresh sorbent

Increment of capture cost

high solid circulation

relevance of understanding hydrodynamics behavior in the CFB’s loop

knowledge of pressure drop along the CFB and seals

control/variation of Gs as function of independent variables

carbonator “internal” circulation effect

Influence on heat transfer in the system

Heat transfer coefficient within each reactor: dense bed and freeboard

Heat transfer between reactors: Sensible heat in the solids is transferred from calciner to carbonator.


Ca looping systems. Objectives

Objectives:


Cold flow and made of Plexiglas for flow visualization

Analyze the pressure drop along the two CFB and loop-seals

Knowledge of the design/controllability of the system

Study the influence of different variables in solid circulation rates

Increase carbonator circulation rates to increase capture efficiency

Analyze the system performance with design modifications


CFB looping. Description

Two Plexiglas risers

4 m height and 160-170 mm i.d.

Recycle systems include:

two HE cyclones

80 mm i.d. 1447 mm height Plexiglas standpipe

177 mm i.d. 300 mm height cylindrical Plexiglas loop-seal

return pipe made of translucent flexible plastic.

Fluidizing air is supplied by blower

nominal flow volume 360 Nm3/h

nominal pressure of 1365 mm w.c



An electric resistance for heating purposes

increase calciner fluidizing air temperature and maintain dimensional similarity

1,5m-long electrical resistance of 3x2200W controlled by a PID temperature controller

Control valves for fluidizing air (risers and loop-seals)

Dynamic pressure measuring and recording system, measurement devices and ancillaries


Ca looping systems. Description

Instrumentation

10 inductive differential pressure transducers (Testo 6340)

connected by means of 4mm i.d. silicone tubes

at different points of the CFB loop,

Pressure transducers are protected by a wire net to inhibit entry of powder from the risers

2 temperature measurements at the entrance of fluidizing gas

Temperature is measured by a PT100 prior entering the calciner riser

2 hot-wire anemometers to monitor gas velocities.

The transmitters output to a multi-channel data-logger Agilent® 34670A (34901A 20-channel general purpose multiplexer) processed by means of the Agilent® software package

Solid circulation rate is measured by flow diversion in the return pipe which connects the loop-seals and the bottom bed of the CFB








Test plan

CFB´s characterization (carbonator and calciner at different Tin)

P= f(h, ur, uls, Gs, solid inventory, Tin, …)

Gs= f(ur, uls, solid inventory, Tin, …)

CFB loop analysis



CFB with internal recirculation



Cyclone P= f(Gs, …)


INDEX

CIRCE description

Ca looping cycles

Introduction

Objectives


Test plan


Objectives

Results


Energy integration of Ca looping systems. Objective

Objective

design a highly integrated process to capture CO2 from an existing power plant based on carbonation/calcination cycle

retrofit scheme that integrates the energy released by carbonation–calcination capture cycle in a supercritical steam cycle

Carbonator (Q1)

Flue gases from carbonator (Q2)

Flue gases (CO2) from calciner (Q3)

Purge (Q4)


Energy integration of Ca looping systems. Results

Existing supercritical coal power plant without desulphurization unit of 427.5 MW net output (450.0 MW gross output).

Energy integration from:

carbonator (Q1= 292MWth)

flue gases from 650ºC to 150ºC (Q2= 232MWth)

CO2 stream from the calciner at 875–950ºC (Q3= 163MWt h).

solid purge heat exchanger (Q4= 33 MWth).

Calciner energy requirements 728.6MWth

coal mass flow rate of 28.8 kg/s

oxygen flow rate of 58.9 kg/s

172.5 kg/s of near-pure CO2

Purge of 48.9 kg/s of deactivated CaO, CaSO4 and ashes


Energy integration of Ca looping systems. ResultsCarbonator (Q1)

Flue gases from carbonator (Q2)

Flue gases from calciner (Q3)

Purge (Q4)


Energy integration of Ca looping systems. ResultsLive steam is 186.5 kg/s and avoid the need of an extra boiler

Gross power output, 308.5MW. Gross efficiency of 42.51%

Three additional heat exchangers have been placed to:

Preheat coal, CaCO3 and oxygen using heat from the hot CO2 stream, flue gases and CaO purge.

Solids are heated up to 130ºC and oxygen up to 80ºC and gases reduce temperature to 130ºC and ashes to 120ºC.

Auxiliary consumption:

Air separation unit 46.6 MWe

52.8 MWe for new fans, solid and gases circulation, CO2 compression

usual power plant auxiliaries 15.4 MW.

Net power output 193.6MWe. Net efficiency 26.68%

Original situation: 333.8 tonCO2/h to produce 427.5MWe (0.781 kgCO2/net kWh)

Integrated system:79.5 tonCO2/h to produce 621.1MWe (0.122 kgCO2/net kWh)



Luis M Romeo ([email protected])Pilar Lisbona, Ana Martínez, Yolanda LaraCIRCE - Center of research on energy

resources & consumption

4th International Workshop on In-Situ CO2 Removal, Imperial College (London), July, 2008



100 kWt O2/CO2 bubbling fluidized bed







2.7 m height, 23 cm i.d. FB water cooling

2 x 200 litres for fuel feeding (coal, sorbent, biomass)

CO2/O2 mixer and flue gas recirculation

Preheating of fluidising gas

Gas cleaning: cyclone and fabric filter

Recycling ratio: from 0% to 80%

O2 in the mixture: from 20% to 40%CoalCoal

++BiomassBiomass

AirAir

Electric Electric PowerPower

Flue gasesFlue gasesCO2, H2O,...

COCO22

CompressionCompressionand dehydrationand dehydration

COCO22 transport transport and storageand storage

Air Air Separation Separation Unit (ASU)Unit (ASU)

OO22

COCO22 recirculationrecirculation

CoalCoal++

BiomassBiomass

AirAir

Electric Electric PowerPower

Flue gasesFlue gasesCO2, H2O,...

COCO22

CompressionCompressionand dehydrationand dehydration

COCO22 transport transport and storageand storage

Air Air Separation Separation Unit (ASU)Unit (ASU)

OO22

COCO22 recirculationrecirculation


selected, recent papers:

Romeo, L.M., Lara, Y., Lisbona, P., Escosa, J.M. 2008. Optimizing make-up flow in a CO2 capture system using CaO. Chemical Engineering Journal, Accepted for publication (2008)

Lisbona, P. Romeo, L.M. Enhanced Coal Gasification Heated by Unmixed Combustion integrated with an Hybrid System of SOFC/GT. International Journal of Hydrogen Energy, Accepted for publication (2008)

Romeo, L.M., Abanades, C., Escosa, J.M., Pano, J., Giménez, A., Sanchez-Biezma, A., Ballesteros, J.C. Oxyfuel carbonation/calcination cycle for low cost CO2 capture in existing power plants. Energy Conversion and Management, doi:10.1016/j.enconman.2008.03.022 (2008)

Romeo, L.M., Espatolero, S., Bolea, I. Designing a supercritical steam cycle to integrate the energy requirements of CO2 amine scrubbing. International Journal of Greenhouse Gas Control, doi:10.1016/j.ijggc.2008.03.002(2008)

Romeo, L.M., Bolea, I., y Escosa, J.M. Integration of power plant and amine scrubbing to reduce CO2 capture costs. Applied Thermal Engineering, 28, 1039–1046 (2008)

Abanades, J.C., Grasa, G., Alonso, M., Rodriguez, N, Anthony, E.J., Romeo, L.M. Cost Structure of a Postcombustion CO2 Capture System Using CaO. Environmental Science and Technology, 41, 15, 5523-5527 (2007)


selected, recent papers:

Romeo, L.M. y Gareta, R. Fouling Control in Biomass Boiler. Engineering Applications of Artificial Intelligence, 19, 8, 915-925 (2006)

L. M. Romeo, R. Gareta. Neural Network for Evaluating Boiler Behaviour. Applied Thermal Engineering, 26, 14-15, 1530-1536 (2006)

R. Gareta, L.M. Romeo, A. Gil. Forecasting of Electricity prices with Neural Networks. Energy Conversion and Management Journal 47, 1770 (2006)

J. Pallarés, I Arauzo, L. I. Díez. Numerical prediction of unburned carbon levels in large pulverized coal utility boilers. Fuel 84, 2364 (2005).

E. Teruel, C. Cortés, L.I. Díez, I. Arauzo. Monitoring and Prediction of Fouling in Coal-Fired Utility Boilers Using Neural Networks. Chemical Engineering Science 60, 535 (2005)

L. I. Díez, C. Cortés, A. Campo. Modelling of pulverized coal boilers: review and validation of on-line simulation techniques. Applied Thermal Engineering 25, 1516 (2005)

R. Gareta, L. M. Romeo, A. Gil. Methodology for the economic evaluation of gas turbine air-cooling systems in combined cycle applications. Energy 29, 1805 (2004)

Center of research on energy resources & consumption Test Facility for the Hydrodynamic Characterization of two CFB for Ca Looping Systems Luis M Romeo.

Documents

center of research

energy applications

ca looping systems luis

ca looping systems cold

objectives objectives

introduction carbonate

c slide

reaction cfb