LINDE s activities for design and development of the processing unit in the Oxyfuel power plant Roland Ritter, Linde-KCA Dresden GmbH Yeppoon, 2 nd Oxyfuel Combustion Conference, S eptemper 14 th 2011, plenary session 3
Agenda 1. LINDE s way to NOx and SOx removal unit LICONOX 2. Using as refrigerant and the integration of expansions-turbines 3. Possible heat integration 4. Change to increase the -recovery rate Pressure swing adsorption unit 5. Dynamic simulation 2
Development of the Linde-concept removal of NOx Boiler SCR Dust removal Desulphurisation unit - Compression High dust -recirculation state of the art researched technologies in LINDE-laboratory: 1) catalytic reduction technology with reduction media hydrogen and ammonia 2) alkali based wash unit with ammonia, sodium hydroxide and ammonia derivate (urea) 3) reduction/ regeneration of spent salt solution Raw gas compression catalytic reaction with hydrogen or ammonia Reduction N 2 NO Self introduced Oxidation 2 NO + O 2 2 NO 2 NO + NO 2 Absorption salt solution (nitrit, nitrat) Alkali based wash unit + Ammonia or NaOH Oxidation Fertilizer (Nitrat) 3
LINDE-concept alkali wash unit ( cold DeNOx ) LICONOX Boiler Dust removal Desulphurisation unit -precompression DeNOx unit -final compression -recirculation NO and SO 2 Oxidation: NO+½ O 2 NO 2 pre-purified, compressed gas s mall gas s tream (low volume flow rate) SO 2 + NO 2 SO 3 + NO smaller equipment Alkali based wash unit: SO 2 + 2 NH 3 + H 2 O (NH 4 ) 2 SO 3 SO 3 + 2 NH 3 + H 2 O (NH 4 ) 2 SO 4 high conversation rate parallel removal of S O 2, S O 3, NO and NO 2 with ammonia water NO + NO 2 + 2 NH 3 + H 2 O 2NH 4 NO 2 reaction of NO and NO 2 2 NO 2 + 2NH 3 + H 2 O NH 4 NO 2 + NH 4 NO 3 2 NO +O 2 + 2 NaOH NaNO 2 + NaNO 3 +H 2 O 2 NO 2 + 2 NaOH NaNO 2 + NaNO 3 +H 2 O Regeneration/ reduction: NH 4 NO 2 N 2 + 2 H 2 0 (Nitrite-decompos ition > 60 C) reaction of S O 2 and S O 3 results are nitrite and nitrate reaction to a mix of nitrogen and sulfur fertilizer reduction to N 2 and H 2 O pos s ible (Denitrification) 4
Test phase on the alkali wash unit simple process flow diagram first test phase: AI PC TC gereinigtes Rauchgas 27.07. 07.09.2010 using ammonia water PDI FC SC laboratory results confirmed 7 x 4 x AI TI NOx PDI T701 FI P702 M Make-up Wasser P703 D701 FI M TC SC Ammoniakwasser Kühlwasser FC AI TI E701 Rauchgas Abwasser LC P701 AC ph M AI second test phase: 26.04. 27.05.2011 (1) reduction of spent salt solution (2) using sodium hydroxide 5
LICONOX - results of pilot plant NOx [vppm] 180 160 140 120 100 80 60 40 20 0 Simulation and Comparison with measured Data 10bar; 24 C; 6,5vol% O2; ph6,5 0 5 10 15 20 25 30 time sec. Extended Kinetic Model nitrogen monoxide nitrogen dioxide nitrite selectivity 1 0,9 0,8 0,7 0,6 0,5 nitrite selectivity [mol/ mol] NOx conversation rate versus pressure NOx conversion pilot plant 100% 95% 90% 85% 80% 75% 70% 65% 60% 55% 50% 0 5 10 15 20 pressure in bar nitrite s electivity vers us NO -NO 2 rate on column entry Consideration of NO 2 yield and influence onto NO conversion Determination of kinetic rate constants Nitrite selectivity forecast Good correlation between measured data and kinetic model 6
Reduction of spent salt solution purified -Gas Make up Water 800 Nitrite-content after reduction vers us temperature 700 compressed -Gas Ammonia Water Cooling Water Nitrit reduction HNO 2 mmol/ l 600 500 400 300 ph 7.2 ph 7.6 ph 7.8 200 Spent salt Solution (Nitrat) 100 0 0 50 100 150 200 Temperture C pos s ible reduction of s pent s alt s olution: NO-NO 2 removal with 15wt% - ammonia water 100% (Basis) NO-NO 2 removal with 33wt% - s odium hydroxide ca. 46% NO-NO 2 removal with ammonia water and reduction ca. 23% 7
Scale up demonstration plant NO x conversion pilot plant 100% 75% 50% 25% % of total NOx 100% 90% 80% 70% 60% 50% 40% 30% Simulation: Washer Implementation after 4th Compression Stage NO NO2 0% 0% 25% 50% 75% 100% NO x conversion simulated Kinetic model confirmed 20% 10% 0% Battery Limit 8 1. compression stage 2. compression stage 3. compression stage plant location 4. compression stage Model based determination of NO/NO 2 profile Selection of DeNOx position Performance simulation based on kinetics for demonstration plant Column height and diameter determination for NOx removal DeNOx
Concept for plant cryogenic separation Raw Gas from Oxyfuel Boiler CW DCC Chilled Water Vent Gas to Atmosphere Pre- Compression CW Drying by Adsorption Process Water Steam Condensate Regen. Gas Heater Product to Pipeline CW Product- Compression simple process Purification multi stream heat exchanger no refrigeration unit necessary partly condensation of in raw gas expansion of the liquid phase close to the triple point of pressure expansion valves application of expansions turbines Activated Carbon Product to Product-Compression Product-Pre- Compressor 9 CW Separator II Booster II/ Turbine II Vent Gas to Regeneration Heat Exchanger Separator I Raw Gas from Drying Stage Booster I/ Turbine I
Cryogenic separation energy optimisation Product to Product-Compression Product-Pre- Compressor CW Booster II/ Turbine II Vent Gas to Regeneration Heat Exchanger Raw Gas from Drying Stage Booster I/ Turbine I installation of two turbinebooster combination expansion of vapor phase in two stages (compression energy) reheating of the cold vapor (refrigeration capacity) Separator II Separator I installation of a productpre-compressor to bring both product streams to the same pressure level 10
Application of valve and turbine expansion Expansio n by Valve Inlet Outlet Inlet Expansio n by Turbine Outlet 11
Possible Heat Integration Heat integration will be optimized in the total oxyfuel process flue gas cooling plate heat exchanger for heating of BFW pre-compression compression with intermediate cooling temp. level of after compression 70 100 C cooling after every second compression stage temp. level of after compression 160 200 C heating of B F W but: higher electric energy consumption for the driver (lower efficiency) final -product-compression without intermediate cooling 12
Increasing of -recovery rate using PSA-unit Application for requirement of high recovery rates Product to Product-Compression CW Compressor Raw Gas from Drying Stage maximum 99% higher spec. energy cons umption (additional recycle) Product-Pre- Compressor Booster II/ Turbine II Heat Exchanger Pressure Swing Adsorption Unit Vent Gas for Regeneration and Recycle before Pre-compression N 2, O 2, Ar Possibility to ASU Separator II Separator I installation of a pressure swing adsorption unit -rich fraction for regeneration and fed back into proces s before pre-compres s ion -lean fraction could be fed to the AS U 13
Dynamic modeling of Oxyfuel power plant Requirement of performance Transmission code 2000 high flexibility of power stations; extreme changing of power load (4 6%/ min) especially with high renewables day and night load Dynamic simulation is key technology in the execution of Oxyfuel power plant Goals of dynamic modeling: ens ure robus t des ign of the plant improve process efficiency Load change evaluation disturbance analyses C ontrol des ign and tuning S tart-up and s hut-down analys es better knowledge of transient plant behaviour in the close connection of all separated plants 14
Dynamic Modeling and Simulation Novel CCS processes pose challenges to plant engineering ue Gas G U e ts n 15
A common intuitive HMI for dynamic process analysis is essential for collaboration among subject matter experts HMI (human machine interface) - process Overview Screen 16
Reduced models for plant-wide simulation of oxyfuel plants develop black box models with minimal number of inputs and outputs Objective: S tudy overall performance of Oxyfuel proces s, by linking models from different tools, e.g. UniSim, OPTISIM (Linde-internal), Constraints: K now-how protection, reas onable computing times P latform-independent model representation based on black-box models (reduced models ) E xample: S ystem Identification for GPU model AS U Model GPU model input: F lue gas condition GPU model outputs: -P roduct and vent gas condition -Feed header pressure -C ompression power demand G P U Model B oiler Model 17
Thank you for your attention Roland Ritter LINDE-KCA DRESDEN GmbH phone +49-351-250 3267 roland.ritter@linde-kca.com