CO 2 capture research at Chalmers Filip Johnsson Department of - PowerPoint PPT Presentation

Chalmers University of Technology CO 2 capture research at Chalmers Filip Johnsson Department of Energy and Environment, Energy Technology 412 96, Göteborg filip.johnsson@chalmers.se SIAMUF – Seminarium Flerfasströmning – Tema Energi

Chalmers University of Technology Outline • Introduction • Oxyfuel combustion • Chemical looping combustion

Chalmers University of Technology Alternatives towards Sustainable Energy Systems - General • To use less energy – Population We need all! We need all! – Technology – Affluence and life style – Efficiency measures • To shift fuel – Renewable energy – Nuclear – Coal to gas • To Capture and Store CO 2 – From large point sources (power plants, industry, hydrogen from fossil fuels) – Carbon sequestration (Land Use Change and Forestation- LUCF)

Chalmers University of Technology Example China • Around 300 GW coal based power being added 2006-2010 ! 700 Mt coal ! 1.7 Gt CO 2 • Similar to the EU targets on emission reductions until 2020 (1.1 – 1.7 Gt)!

Chalmers University of Technology CO 2 Capture, Transport & Storage (CCS)

Chalmers University of Technology Three main principles for CO2 capture

Chalmers University of Technology Planned and proposed CCS demos

Chalmers University of Technology Oxyfuel combustion

Chalmers University of Technology The basic principle of oxy-fuel combustion Typically 2/3 of the flue gas is recirculated recirculated Typically 2/3 of the flue gas is

Chalmers University of Technology Conditions in oxy-fuel combustion Table 1. Rough overview of properties of the flue gas in an oxy-fuel power plant (see Figure 1 for stream numbers). ! Stream 1 2 3 4 5 6 7 Pressure (bar) 1 1 1 30 30 100 1 Temperature (°C) 300 300 20 20 -30 20 20 Mass Flow 1 1/3 1/3 1/3 1/4 1/4 1/25 Volume Flow 1 1/3 1/7 1/200 1/900 1/1000 1/40 Fluid * Phase Gas Gas Gas Gas Liquid Gas * Supercritical fluid.

Chalmers University of Technology First assessment of the oxfuel process - reference power plant Lippendorf Lignite-fired 2x865 MW el , ! el =0.426 Comissioned in 2000 10 million tonnes CO 2 /year

Chalmers University of Technology Process layout of the O 2 /CO 2 Power Plant C 16 14 13 21 Flue gas treatment 19 12 15 17 20 18 CO 2 22 out 32 B 31 11 24 25 23 Power plant 10 27 26 30 29 9 28 o 2 O 2 N 2 A 8 6 5 Air Separation Unit 7 o 2 4 1 2 3 Air inlet

Chalmers University of Technology The CO2 avoidance cost w – with capture, w/o – without capture " ( EUR / MWh ) ( EUR / MWh ) w w / o " ( tonne CO / MWh tonne CO / MWh ) 2 w / o 2 w # approximately 20 Process analysis # approximately 20 € € /tonCO /tonCO 2 Process analysis 2 (depends on interest rate and fuel price!) (depends on interest rate and fuel price!)

Chalmers University of Technology Aim and focus of the Oxy-fuel group Aim: To provide fundamental knowledge on oxy-fuel combustion required for design, scale-up and optimization of oxyfuel combustion process Focus: Combustion experiments & modeling Combustion experiments & modeling " Heat transfer " Heat transfer " Chemistry Chemistry " " Mixing Mixing " Primary and secondary measures Primary and secondary measures for pollutant control for pollutant control

Chalmers University of Technology Oxyfuel – Intense development Coal from pneumatic feed system Dry, pressurized flue gas as carrier gas Coal feed Direct O2 injection Primary/secondary register mixing point FI TI Pilot burner air/O2/CO2 fan O2/flue gas Air inlet pre-heater SC FI FI Wet flue gas Dry flue gas FI FI recycle recycle Cylindrical Measurement furnace ports R1, R2...R7 SC 2400 mm Cooling tube 1/4 TI PIC FI Flue gas Fabric Flue gas cooler Stack gas 800 mm Filter condenser TI TC TC C 3 H 8 O 2 Dry, pressurized flue gas for dust Cooling water control and fuel carrier gas Small pilot (Chalmers 100 kW) Small pilot (Chalmers 100 kW) Lab scale (IVD 10 kW) Lab scale (IVD 10 kW) Basic research Basic research Basic research Basic research Pilot/Demo (Vattenfall Pilot/Demo ( Vattenfall 30 MW) 30 MW) Demo/full scale (2015- Demo/full scale (2015 -2020?) 2020?) Testing of new products (2008) Testing of new products (2008) Early market introduction Early market introduction

Chalmers University of Technology The oxyfuel group – main methodologies • Experiments – 100 kW Chalmers oxyfuel unit – Vattenfall 30 W Schwartze pumpe pilot plant – To come: CFB test unit in Tampere • Modeling – Reaction kinetics etc – CFD simulations • Process simulations

Chalmers University of Technology Procedure • Scale up effects from the Chalmers 100 kW unit to the 30 MW pilot plant (Schwartze Pumpe) • Scale up to unit of commercial size (“conventional oxyfuel 25-30% O2 in RFG) • Innovative oxyfuel boilers with higher O2 in RFG Change in conditions have implications for in-furnace processes as well as downstream processes which in turn yield differences in optimal combination of primary and secondary flue gas cleaning measures

Chalmers University of Technology Chalmers 100 kW oxyfuel test unit 100kW Lignite flame 100kW Lignite flame 27% oxygen 27% oxygen

Chalmers University of Technology Test unit and measurements Coal from pneumatic feed Measurements: system Dry, pressurized flue gas as carrier gas Coal feed Direct O2 injection Radiation intensity Primary/secondary register mixing point FI TI air/O2/CO2 fan Pilot burner O2/flue gas Air inlet Gas temperature pre-heater SC FI FI Gas composition Wet flue gas Dry flue gas FI FI recycle recycle Cylindrical Measurement furnace ports R1, R2...R7 SC 2400 mm Cooling tube 1/4 TI PIC FI Flue gas Fabric Flue gas cooler Stack gas 800 mm Filter condenser TI TC TC C 3 H 8 O 2 Dry, pressurized flue gas for dust Cooling water control and fuel carrier gas

Chalmers University of Technology Measurements 1620 mm 4 mm • Gas concentration profiles: Cooling water outlet A Ø45,0/41,0mm Ø33,0/29,0mm Online analysis: O 2 , CO, HC, Heated tube: Ø18,0/14,0mm to prevent Ø8,0/6,0 mm condensation CO 2 , NO x , (SO 2 ) Gas suction tube A Section A-A Cooling water inlet 1900 mm • Temperature profiles: Suction inlet A Cooling water outlet flue gas: D=6mm Thermocouple Ø45,0/41,0mm Type B: D=3mm Ø30,0/26,0mm suction pyrometer Ø17,2/13,0mm 10,0x1,0 mm TC: S and B (~2000K) 200mm Ø13,0mm A Cooling water inlet Section A-A High broadband Electronic reflectance mirror shutter • Radiation intensity profiles: Collimating tube Narrow angle radiometer Line-of-sight intensity Cooling water Cooling PT-100 Thermopile water Experimental set-up

Chalmers University of Technology Nitrogen oxides

Chalmers University of Technology NO x in oxy-fuel combustion Principle changes: Concentration of N 2 O 2 Recycle of flue gas COAL Concentration of combustion products RECYCLE Residence time Temperature NO x

Chalmers University of Technology HTNR vs. Reburning NO in = 1000ppm N 2in = 0% Reverse O 2 /CO 2 Reburning Zeldovich t = 1 s # = 0.9 No Fuel-N Figure: Normann. F, Andersson, K, Leckner, B, Johnsson, F, Fuel 87 (2008) 3579–3585, 2008 NO x

Chalmers University of Technology NO x reduction options in oxy-fuel combustion Advantages Disadvantages NO x red. Primary Measures Reburning Proven technology Natural gas consumption 50-60% a Staging Proven technology Reduced combustion efficiency 10-40% a Low-NOx burner Proven technology Reduced combustion efficiency 20-60% a Flue gas recycling Included in the oxy-fuel process ~70% b Improved combustion High-Temp. efficiency/new boiler Melting of ashes/new boiler -90% c Secondary Measures SCR Proven technology Catalysts/ammonia cons./units 80-95% a SNCR Proven technology Ammonia consumption/slip 30-50% a Lead Chamber/NO 2 absorption Simultaneous removal of SO x Extra units -90% c Placed in high-pressure part Waste; weak nitric acid Co-storage Included in the oxy-fuel process Pollution of the CO 2 -95% c Distillation Simultaneous removal of SO x Power consumption -95% c NO x

Chalmers University of Technology Summary - NOx Several techniques available to reduce NO x in oxy-fuel combustion Reduction via secondary measures may not be required The formation and reduction mechanisms should be investigated further to allow optimization of primary/secondary measures both high and low NO x levels at the furnace exit may be of interest The NO x formation in industrial scale oxy-fuel burners need to be studied and compared against results in lab-scale units NO x

Chalmers University of Technology Radiative heat transfer

Chalmers University of Technology Chalmers University of Technology Radiative heat transfer of major importance in design of furnaces Changed combustion conditions will affect the gaseous radiation Longer pressure path lengths Longer pressure path lengths Different ratio of H 2 O/CO 2 Different ratio of H 2 O/CO 2 influence of increased gas radiation when it competes with particle radiation? Gas vs. particle radiation in propane and lignite flames Radiation