Fluidized Bed Based CO 2 Capture by Carbonate Looping Prof. Dr.-Ing. Bernd Epple bernd.epple@est.tu-darmstadt.de www.est.tu-darmstadt.de Tel. +49 6151 16 4717 1
Carbonator: T 450 750 C CaO + CO 2 CaCO 3 Carbonator Combustor Coal Air CaCO CaO 3 Calciner CO 2 Calciner: T > 850 C CaCO 3 CaO + CO 2 Carbonate Looping CFB 2
Electrostatic Precipitator Carbonator 650 C Q 1 CO 2 - reduced flue gases CaO CO 2 CaCO 3 CaCO 3 Source: Romeo, Abanades, Ballesteros et al CaCO 3 CaO +CO 2 CO 2 + CaO CaCO 3 Q 2 Q 4 Calciner 900 C Fuel ID-Fan Limestone based CO 2 Capture Cycle : General Layout O 2 CaO Q 3
- Less energy intensive, minor plant cycle efficiency losses compared to other CO2 capture processes Efficiency Loss incl. CO2 Compress. (100 bar, 30 C) (Carbonate Loop. 5-8 %, Oxyfuel bis 13 %; MEA bis 14 % ) - CO2 Avoidance Costs far below 20 / t CO2 - retrofit option for existing plants - (treatment of flue gas with temp. of 110-170 C possible) - combination of two Circulating Fluidized Bed Units (Carbonator, Calciner) - non-toxic agents (limestone, dolomite) with high availability - spent agents can be used in cement industry - no waste water treatment necessary SUMMARY: FEATURES OF THE PROCESS (CO2 Capture by Carbonate Looping) 4
Externally heated glass tube filled with absorbent Reactivity tests of different absorbents (limestone, dolomite) CO 2 absorption rate at several temperatures (450-750 C) Reactivity decrease of limestone cyclic operation Glass tube 30 mm Absorbents Electr. heated Oven Laboratory Scale : Limestone Reactivity Tests 5
Coarse Crystal Structure Fine Crystal Structure Limestone Particle Structure 6
Limestone Kalkreaktivitätstest, Reactivity Test Carbonisierung - Carbonisation Maximum max.carbonisierungsausbeute carbonisation efficiency (mol-%). 80 70 60 50 40 30 20 10 0 1 2 3 4 5 6 7 8 9 10 Zyklus No. of cycles Daloba-650 Öskü-650 12MX1-650 Decrease of Reactivity by Cyclic Operation Source: Epple TU Darmstadt 7
800 kw Pulverized Fuel Burner* -> Flue Gas 800 kw CFB Pilot Plant (CFB 600)* -> Carbonator 1500 kw CFB* -> Calciner 800 KW CFB Pilot Plant (CFB 650)* 200 kw Entrained Flow Reactor Cold CFB Test Rig (10 m)* Cold CFB Test Rig (5 m) * Test rigs transferred from Foster Wheeler Test Rigs at TU Darmstadt Campus 8
Top burner Vertical Combustor Flue Gas Heat exchanger Vertical Combustion Chamber + Heat Exchangers (2nd pass)
CFB : 800 kw thermal input 10
Air Coal/ Gasfired 110 C Pulv. Fuel 0.8 MW Carbonization CaO + CO 2-> CaCO 3 CaO CFB Absorber 110 C Cyclone CaCO 3 CaCO 3 Fuel Calciner ~1000 C O 2 Filter Cyclone CaO, CaCO 3 CO 2 H 2O N,O 2 2 Source: Epple TU Darmstadt 1 MW EST Test Rig Arrangement: CO 2 Capture by Carbonate Looping 11
1 MW EST Test Rig Arrangement: CO 2 Capture by Carbonate Looping