Progress in Modelling of IGCC Components

Transcription

1 Progress in odelling of IGCC Components D. Korobov, B. eyer, S. Guhl, K. Lorenz, S. Ogriseck, H. Rauchfuß uß International Freiberg Conference on IGCC & XtL Technologies June 17,

2 Principle of IGCC Gasification agent Air Raw gas Fuel gas Coal Gasification Gas treatment Combined cycle Power Ash/Slag Sulphur, optional CO 2 Flue gas odelling tools: ASPEN Plus Fluent Factsage, Simusage Coupled mass and energy balances Fluid mechanics Behaviour of trace components (volatile metals e.g. Na, K, Zn) - 2 -

3 odelling of Gasification Processes (1) Gasification Principles Fixed bed Fluidized bed Entrained flow Increase of raw gas equilibrium temperature approach -3-

4 odelling of Gasification Processes (2) Using of global approach temperature t A t A = t EQ odelling Principles t P Rough forecast of gasification process, if exact process data not available Using of individual approach temperature for each reaction C + CO 2 2CO C + 2H 2 CH 4 C + O 2 CO 2 2C + H 2 + N 2 2HCN S + CO COS S + H 2 H 2 S C + H 2 O CO + H 2 6C + 3H 2 C 6 H 6 3H 2 + N 2 2NH 3 H 2 + Cl 2 2HCl Fine tuning exact process data necessary Adjustment of trace components Solving of coupled material and energy balances - 4 -

5 odelling of Gasification Processes (3) odelling Assumptions Chemical equilibrium Coupled energy and mass balances Carbon losses Tar formation Influence of pyrolysis Basis Operational data (gas quality) ass balance, heat losses (mostly not directly definable) Operational data (carbon balance) Operational data, experiments Theoretical background, experiments odelling Temperature approach Feedstock input, heat losses, variation of steam consumption C conversion, variation of oxygen consumption Assumption of tar composition Experimental data - 5 -

6 odelling of Gasification Processes (4) Example BGL-gasifier drying and pyrolysis t < 700 C gasification t = 700 1,100 C combustion t 2,000 C /Coal Gasification for Towngas Production as easure for Pollution Abatement, Lurgi 2002/ - 6 -

7 odelling of Gasification Processes (4) Example BGL-gasifier long gasification time (hours) three pronounced reaction zones C n H m and tar in gas Calculation of chemical equilibrium for each zone necessary /Coal Gasification for Towngas Production as easure for Pollution Abatement, Lurgi 2002/ - 7 -

8 odelling of Gasification Processes (4) Example BGL-gasifier Usage of individual approach temperatures for each reaction Adjustment of trace components concentration Assumption of tar / dust composition & amount Experiments for pyrolysis zone modelling necessary Hardly transferable results for other fuels Usage of pseudo approach for pyrolysis zone without physical background /Coal Gasification for Towngas Production as easure for Pollution Abatement, Lurgi 2002/ - 8 -

9 odelling of Gasification Processes (5) Pyrolysis input-data: fuel composition yield of char and condensate composition of char and condensate amount of pyrolysis gases output-data: heat of pyrolysis Pyrolysewärmebedarf Pyrolysis heat demand in kj/kg in kj/kg Holz ASPEN DSC Pyrolysis Pyrolysetemperatur temperature in in C C Good correlation between experimental measured heat of pyrolysis (DSC) and calculated values - 9 -

10 Results of Gasification odelling Fixed bed Fluidized bed Entrained Flow Gasification process Fuel Cold gas efficiency Specific Steam consumption kg/kg daf BGL HTW Shell Waste Lignite Lignite % kg/m³ std,dry Specific O 2 consumption kg/kg daf kg/m³ std,dry Carbon conversion % Specific dry gas production m³ std /kg daf

11 Principle of IGCC Gasification agent Air Raw gas Fuel gas Coal Gasification Gas treatment Combined cycle Power Ash/Slag Sulphur, optional CO 2 Flue gas odelling tools: ASPEN Plus Ebsilon Professional Coupled mass and energy balances, electrolytes Heat recovery, heat integration

12 odelling of Gas Treatment (1) Cooled raw gas C ake-up water to Waste water treatment Waterwash Cold power plant condensate Conventional Gas Treatment IP-Steam Gas preheating IP-Water HCN/COS Hydrolysis Condensate ake-up water Gas cooling C Gas cooling 2 40 C H 2 S- wash Preheating & Saturation to GT Preheated power plant condensate H 2 S to Claus process Gas condensate to waste water treatment

13 Principle of IGCC Gasification agent Air Raw gas Fuel gas Coal Gasification Gas treatment Combined cycle Power Ash/Slag Sulphur, optional CO 2 Flue gas odelling tools: Gate Cycle Ebsilon Professional combined cycle design combined cycle design

14 odelling of Combined Cycle Gate Cycle EBSILONProfessional Combined cycle G D-Dampf (10 bar) ex S-Gewinnung a ke up Wasser für Wasserwäsch Gasreinigung G make-up Wasser Example: Full integrated ASU HRSG with HP, Vergaser IP and HD-N2 zum Vergaser LP steam production D -N 2 zum Vergas er TBK WTA G D-Wasser zum Gasreinigung (Reingassättigung) von S-Gewinnung für DEA Kondensatvorwärmung bei der Gasreinigung für WTA Brüd en RBK LZA R estgas zur GT für Abwasserbehandlung für LZA

15 Q W Temperature (C) Pressure (bar) ass Flow Rate (kg/sec) Duty (Watt) Power(Watt) RGIBBS FSPLIT Auxiliary Units Air Separation Unit eoh Synthesis FLASH OFF-GAS COPR-3 W Q WT-8 COOLER-4 ETHANOL B SPLIT-10 PURGEGAS coldbox FEED ETHANOL 47 RECYCLE HEATER-5 W COPR Temperature (C) Pressure (bar) ass Flow Rate (kg/sec) RECYCLE1 RGIBBS Temperature (C) Pressure (bar) ass Flow Rate (kg/sec) Q Duty (W) Claus-Unit ulti staged CO 2 -Compression

16 Results Calculation results for complete IGCC with/without CO 2 -separation Basic parameters (Including fluidised bed gasifier, ASU, CO 2 -Separation, CO 2 -compression) Fuel Turbine inlet temperature (iso) Ambient temperature Condenser pressure Power output gross net Own need total Fraction of own need on gross power output Efficiency net CO 2 -Retention & Emission CO 2 -Retention specific CO 2 -Emission With CO 2 -sep. Lignite , Without CO 2 -sep C C mbar 1,036 W W W % % % kg CO 2 / Wh

17 Summary Experiences in modelling of complete IGCC, esp. gasification, and sub systems Selection of most capable components depending on Feed stock quality Site needs Optional CO 2 -Separation Optimised processes for given feed stocks Specialised fuel analysis to gain gasification modelling data

18 Thank you for your Attention!