Anthony, Ben

Jurado Pontes, Nelia

Oakey, John

English

UCL Discovery

Electrochemical NoiseProbeElectrodes section before a testElectrodes section after a testEngineered heat flux sensor (Hukseflux)In-house air-cooled probe for convective heat flux measurement 100% Cereal co-product100% El CerrejonCharacterisation of ash deposits generated co-firing coal and biomass blends under oxy-firing conditions Nelia Jurado  Pontes (n.juradopontes@cranfield.ac.uk)  Ben Anthony John Oakey Delivering Low Carbon Energy from Biomass Resources IChemE, London, UK 8th June 2015 Oxy-combustor facility  Gas analysisTemperature monitoringTemperature monitoringCoolant outCoolant inTemperature monitoringExhaustPulverised coal / biomass/natural gas + CO2/O2 / AirCooling water outCooling water inGas analysisCooling water inCooling water outCycloneAsh removal systemDry GasCooling water inCooling water outCondenser Condensates Recycled Flue GasesPure Oxygen(O2)RCFanIDFanDiagram of 100kWth Oxy-Combustor with Condenser  Oxy-combustor facility PROBES AND LOCATION  Gas analysisTemperature monitoringTemperature monitoringCoolant outCoolant inTemperature monitoringExhaustPulverised coal / biomass/natural gas + CO2/O2 / AirCooling water outCooling water inGas analysisCooling water inCooling water outCycloneAsh removal systemFanFanDry GasCooling water inCooling water outCondenser Condensates Recycled Flue GasesPure Oxygen(O2)Diagram of 100kWth Oxy-Combustor with Condenser  CONDENSER Primary Gas Composition sampling point Secondary Gas Composition sampling point New calibration model needed for the FTIR (Higher concentrations of  CO2 expected) Retrofitting Process LATEST MODIFICATIONS Retrofitting Process LATEST MODIFICATIONS Location of the sampling point 260oC 75-85 oC SO3 AND SULFATES MEASUREMENT  (Controlled Condensation Method) Experimental conditions Type of  fuel: El Cerrejon Coal 13.5kg/h    75% El Cerrejon -25% CCP 15kg/h     50% El Cerrejon -50% CCP 16.7kg/h     Cereal  co –product  22kg/h  Percentage of  Recycled Flue Gas :60-65%  Types of Recycled Flue Gas Wet- Hot Recirculation (After Particle Removal ) Dry – Cool Recirculation (After Particle, Condenser) Oxygen Injection Primary O2 (Fuel carrier draught): Not Used   Secondary O2: 34-38% in gas supplied  Experimental conditions FUEL ANALYSIS   El Cerrejon coal Cereal co-product Proximate analysis (% (wt) as received)     Moisture 5.80 8.10 Volatile matter 34.80 70.80 Ash 8.60 4.20 Calorific value, (MJ/kg)      Gross calorific value 27.85 17.61  Net calorific value 27.12 16.34  Ultimate analysis (% (wt) as received)     Carbon 69.2 43.30 Hydrogen 4.40 5.80 Nitrogen 1.42 2.70 Chlorine 0.02 0.17 Sulfur 0.58 0.16 Oxygen 9.98 35.57 Ash analysis (% (wt))     SiO2 60.69 44.36 Al2O3 22.01 2.79 Fe2O3 7.43 2.47 TiO2 0.92 0.12 CaO 2.27 7.78 MgO 2.90 3.96 Na2O 1.06 0.36 K2O 2.32 24.72 Mn3O4 0.06 0.10 P2O5 0.21 12.04 SO3 - - BaO 0.11 0.05 Experimental conditions FUEL ANALYSIS   El Cerrejon coal Cereal co-product Proximate analysis (% (wt) as received)     Moisture 5.80 8.10 Volatile matter 34.80 70.80 Ash 8.60 4.20 Calorific value, (MJ/kg)      Gross calorific value 27.85 17.61  Net calorific value 27.12 16.34  Ultimate analysis (% (wt) as received)     Carbon 69.2 43.30 Hydrogen 4.40 5.80 Nitrogen 1.42 2.70 Chlorine 0.02 0.17 Sulfur 0.58 0.16 Oxygen 9.98 35.57 Ash analysis (% (wt))     SiO2 60.69 44.36 Al2O3 22.01 2.79 Fe2O3 7.43 2.47 TiO2 0.92 0.12 CaO 2.27 7.78 MgO 2.90 3.96 Na2O 1.06 0.36 K2O 2.32 24.72 Mn3O4 0.06 0.10 P2O5 0.21 12.04 SO3 - - BaO 0.11 0.05 Experimental Results GAS COMPOSITION 0102030405060708090 CO2 max [db] CO2 max [wb]CO2( wb) O2 H2O2013 O-F EL CERREJON 100% (I) 2013 O-F EL CERREJON 100% (II) 2013 O-F EL CERREJON 100% (III)2013 O-F EL CERREJON 75% - CCP 25% 2013 O-F EL CERREJON 50% - CCP 50% (I) 2013 O-F EL CERREJON 50% - CCP 50% (II)2013 O-F CCP 100% (I) 2013 A-F EL CERREJON 100% 2013 A-F EL CERREJON 50% - CCP 50%2013 A-F CCP 100%GAS COMPOSITION-Main Species% v/v Maximum CO2 : 57-62% wet basis [80-81% (d. b.)]   H2O ~ 20-29% (v/v)    O2~ 4.3% (v/v)    0200400600800100012001400NOx CO SO2 HCl CH4 SO2[CCM]SO3[CCM]2013 O-F EL CERREJON 100% (I) 2013 O-F EL CERREJON 100% (II) 2013 O-F EL CERREJON 100% (III)2013 O-F EL CERREJON 75% - CCP 25% 2013 O-F EL CERREJON 50% - CCP 50% (I) 2013 O-F EL CERREJON 50% - CCP 50% (II)2013 O-F CCP 100% (I) 2013 A-F EL CERREJON 100% 2013 A-F EL CERREJON 50% - CCP 50%2013 A-F CCP 100%GAS COMPOSITION- Minor  speciesppmv SO2 coal 750ppmv   blends 550ppmv   biomass 100ppm  NOx  550-750 ppmv  CO 400 ppmv  HCl coal 6-20 ppmv   biomass 100ppm Experimental Results GAS COMPOSITION SO2_FTIR (ppmv) SO2_CCM (ppmv) (SO3+SO42-)_CCM (ppmv) (SO3+SO42-)/SO2 (%) Air-firing El Cerrejon 305.2 83.5 3.0 3.6 Air-firing 50%EC-50%CCP 274.3 245.8 16.6 6.7 Air-firing CCP 87.6 98.9 20.8 21.0 Oxy-firing El Cerrejon 819.6 566.8 16.9 3.0 Oxy-firing 75%EC-25%CCP 654.3 525.2 13.8 2.6 Oxy-firing 50%EC-50%CCP 442.2 231.4 29.5 12.7 Experimental Results SO3 & SULFATES Effect of  fuel: SO3+SO42- levels rising as the share of  CCP increases    Alkalis reaction with SO3 to generate sulfates    SO2 to SO3 promoted by alkalis Effect of  firing mode: SO3+SO42- levels in oxy-firing higher than in air-firing Experimental Results ASH DEPOSITS a) b) c)d) e) f)a) Air- firing El Cerrejon b) Air-firing 50%EC-50%CCP c) Air-firing CCP  d) Oxy- firing El Cerrejon e) Oxy-firing 50%EC-50%CCP f) Oxy-firing CCP The structure of  the deposit is more fibrous and porous using 100% CCP than when oxy-firing 100% El Cerrejon coal or the coal-biomass blends. No significant difference in the aspect of  the deposits can be observed comparing the cases under oxy and air-firing conditions. Experimental Results ASH DEPOSITS El Cerrejon coal & CCP 05101520253035404550O Na Mg Al Si P S K Ca Ti Fe Cu Cl Ba Cr O-F EL CERREJON 100% O-F EL CERREJON 100% O-F EL CERREJON 75% - CCP 25%O-F EL CERREJON 50% - CCP 50% O-F EL CERREJON 50% - CCP 50% O-F CCP 100%% (Weight)ElementASH DEPOSITS-High T (750ºC) ProbesKey findings- Experimental Gas composition  CO2   >80% (db) for pure coal and pure biomass  H2O 20-29%, even with dry recycle NOx 550-750ppmv SO2 100-750ppmv HCl 8-100ppmv SO3+SO42- 14-30ppmv   Clear increase in (SO3+SO42-)/SO2 ratio when   %CCP Ash deposits Markedly  fibrous and cohesive for high shares of  CCP Similar S levels for pure coal and biomass (K2SO4 generation) Chloride only observed in ash deposits from pure CCP Difficulty to control the %RFG when using coal-biomass blends and pure biomass (liquid accumulation in the condenser)  The ηcondenser dropped sharply after two hours of operation  Dry recycle used from the start of the tests with 100% biomass (otherwise minimal efficacy)   Some air ingress into the process through the deposit probes (due to cooling air)  Appropriate maintenance of heat flux sensor  Decrease of air ingress from 10% to 5% (improved sealing of the facility and operation at slightly positive pressure)   Operational issues associated to the use of Biomass Future challenges Use of  other fuels:     Further investigation on SO3/SO2 ratios using high shares of  biomass                   Applying identical procedure to EPA-Method 8A (avoiding sulfates interferences)   Coal with higher S levels: effect on SOx generation  Biomass with higher Na contents: effect on ash deposits characteristics Electrochemical NoiseProbeElectrodes section before a testElectrodes section after a testEngineered heat flux sensor (Hukseflux)In-house air-cooled probe for convective heat flux measurement 100% Cereal co-product100% El CerrejonCharacterisation of ash deposits generated co-firing coal and biomass blends under oxy-firing conditions Nelia Jurado  Pontes (n.juradopontes@cranfield.ac.uk)  Ben Anthony John Oakey Delivering Low Carbon Energy from Biomass Resources IChemE, London, UK 8th June 2015 Thanks for your attention 

Characterisation of ash deposits generated co-firing coal and biomass blends under oxy-firing conditions

https://discovery.ucl.ac.uk/10117236/1/IChemE_NJ-public%20access.pdf

Characterisation of ash deposits generated co-firing coal and biomass blends under oxy-firing conditions

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