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Numerical simulation of hydrogen production by chemical looping
Engineering Conferences International ECI Digital Archives Fluidization XV Proceedings 5-24-2016 Numerical simulation of hydrogen production by chemical looping reforming in a dual interconnected fluidized bed reactor Piero Bareschino Dipartimento di Ingegneria, Università degli Studi del Sannio, Italy, [email protected] Roberto Solimene Istituto di Ricerche sulla Combustione, Consiglio Nazionale delle Ricerche, Italy Giuseppe Diglio Dipartimento di Ingegneria, Università degli Studi del Sannio, Italy Erasmo Mancusi Dipartimento di Ingegneria, Università degli Studi del Sannio, Italy Francesco Pepe Dipartimento di Ingegneria, Università degli Studi del Sannio, Italy See next page for additional authors Follow this and additional works at: http://dc.engconfintl.org/fluidization_xv Part of the Chemical Engineering Commons Recommended Citation Piero Bareschino, Roberto Solimene, Giuseppe Diglio, Erasmo Mancusi, Francesco Pepe, and Piero Salatino, "Numerical simulation of hydrogen production by chemical looping reforming in a dual interconnected fluidized bed reactor" in "Fluidization XV", Jamal Chaouki, Ecole Polytechnique de Montreal, Canada Franco Berruti, Wewstern University, Canada Xiaotao Bi, UBC, Canada Ray Cocco, PSRI Inc. USA Eds, ECI Symposium Series, (2016). http://dc.engconfintl.org/fluidization_xv/97 This Abstract and Presentation is brought to you for free and open access by the Proceedings at ECI Digital Archives. It has been accepted for inclusion in Fluidization XV by an authorized administrator of ECI Digital Archives. For more information, please contact [email protected]. Authors Piero Bareschino, Roberto Solimene, Giuseppe Diglio, Erasmo Mancusi, Francesco Pepe, and Piero Salatino This abstract and presentation is available at ECI Digital Archives: http://dc.engconfintl.org/fluidization_xv/97 UniversitàdegliStudidelSannio DipartimentodiIngegneria UniversitàdegliStudidiNapoliFedericoII DipartimentodiIngegneriaChimica,dei MaterialiedellaProduzioneIndustriale NumericalSimulationofHydrogenProductionby ChemicalLoopingReforminginaDualInterconnected FluidizedBedReactor GiuseppeDiglio,PieroBareschino,ErasmoMancusi,FrancescoPepe Università degliStudidelSannio,DING – Benevento (Italy) RobertoSolimene ConsiglioNazionale delle Ricerche, IRC– Napoli(Italy) PieroSalatino Università degliStudidiNapoliFederico II,DICMaPI- Napoli(Italy) Fluidization XV– May 22-27,2016 H2 asfuelcancontributetoreduceCO2 emissions CurrentlyH2 isproducedmainlybySMR - Highlyenergydemand - Need ofpost-processingforCO2 separation CLRcanovercometheseissues Numerical simulation - Whichtypeofreactorconfiguration? - Whichtypeofoxygencarrier? FluidizationXV– May22-27,2016 Literature Most of numerical simulations of CLR in DIFB are focused only on kinetic scheme Whatyouneed? An appropriate hydrodynamic model of the whole system in order to point out “stable” operating conditions. Aim ofthework To develop a simple mathematical tool coupling a CLR reactive scheme and a simple hydrodynamic model of a DIFB system. FluidizationXV– May22-27,2016 1 • FRsplitintwozones:densezonebelowdilutedzone/FreeBoard (FB) 2 • DensezoneismodelledasaCSTR,whileFBismodelledasaPFR 3 • ARismodelledasCSTR(denseregime)orPFR(dilutedregime) 4 • Conversionisuniformthroughoutsolidparticles 5 • IntheFBonlyhomogeneousWGSwastakenintoaccount FluidizationXV– May22-27,2016 𝑚*+, = 𝑚-.- + 𝑚01 + 𝑚" + 𝑚2/04 𝑚-.- = 𝐴-.- ⁄𝑔 ' ∆𝑃-.- DEPLETED AIR 𝑚01 = 1 − 𝜀8 ' 𝜌: ' 𝐴1: ' 𝐿< − 𝐼<> + 1 − 𝜀8 ' 𝜌: ' 𝐴1? ' 𝐼1?+ 1 − 𝜀" ' 𝜌: ' 𝐴"? ' ℎ "? 𝑚" = 𝐴" ⁄𝑔 ' ∆𝑃" 𝑚2/04 = 1 − 𝜀A ' 𝜌: ' 𝐴A ' 𝐿A + 1 − 𝜀4 ' 𝜌: ' 𝐴2 ' 𝐻 ' 𝜂 𝐿4 − 𝐻 + 𝐿4 ' 𝜂 ∗ 𝐻 − 𝐿4 CH4 +CO+CO2 +H2 O+H2 +N2 CH4 +2NiO↔2Ni+2H2 +CO2 H2 +NiO↔Ni+H2 O CO+NiO↔Ni+CO2 𝑑𝑚2/04 = 𝑊" − 𝑊< 𝑑𝑡 CH4 +NiO↔Ni+2H2 +CO !" CH4 +H2 O↔3H2 +CO !" CH4 +CO2 ↔2H2 +2CO !" CO+H2 O↔H2 +CO2 !" 𝑑𝑚" = 𝑊01 − 𝑊" 𝑑𝑡 CH4 +N" ↔Ni-C+2H2 !" C+H2 O↔H2 +CO !" C+CO2 ↔2CO CH4 +H2 O+N2 2Ni+O2 →2NiO AIR 𝑑𝑚01 = 𝑊- − 𝑊0< 𝑑𝑡 FluidizationXV– May22-27,2016 BubblingFluidizedBed(BFB) DEPLETED AIR hp: elutriation is negligible • Massflowrate 0 → ℎ 2,- < ℎ 𝑊- = H 𝑊< → ℎ 2,- ≥ ℎ - CH4 +CO+CO2 +H2 O+H2 +N2 CH4 +2NiO↔2Ni+2H2 +CO2 H2 +NiO↔Ni+H2 O • Pressuredrop ∆𝑃-.- = 𝜌: ' 1 − 𝜀2 ' 𝑔 ' ℎ 2,- CO+NiO↔Ni+CO2 CH4 +NiO↔Ni+2H2 +CO !" CH4 +H2 O↔3H2 +CO !" CH4 +CO2 ↔2H2 +2CO !" CO+H2 O↔H2 +CO2 !" CH4 +N" ↔Ni-C+2H2 !" C+H2 O↔H2 +CO !" C+CO2 ↔2CO CH4 +H2 O+N2 2Ni+O2 →2NiO AIR FluidizationXV– May22-27,2016 LoopSeal DEPLETED AIR Loop Seal works in complete fluidization condition between Supply Chamber (SC) and Recycle Chamber (RC). • Massflowrate 𝑊01 = 𝑊< CH4 +CO+CO2 +H2 O+H2 +N2 CH4 +2NiO↔2Ni+2H2 +CO2 H2 +NiO↔Ni+H2 O CO+NiO↔Ni+CO2 • Aerationgasflowrate 𝑄01 = 𝑄1? + 𝑄"? CH4 +NiO↔Ni+2H2 +CO !" CH4 +H2 O↔3H2 +CO !" CH4 +CO2 ↔2H2 +2CO !" CO+H2 O↔H2 +CO2 !" CH4 +N" ↔Ni-C+2H2 • Gas“leakage” betweenSCandRC 𝑊" ' 𝜀8Q 𝑈0< ≥ 𝑈8Q − 𝐴1? ' 𝜌: ' 1 − 𝜀8Q !" C+H2 O↔H2 +CO !" C+CO2 ↔2CO CH4 +H2 O+N2 2Ni+O2 →2NiO AIR FluidizationXV– May22-27,2016 Riser DEPLETED AIR hp: 1) transition between dense and dilute phase takes place when mass flow rate approaches the value corresponding to its saturation carrying capacity; 2) the variation of voidage along the riser and with the mass flux have been neglected. CH4 +CO+CO2 +H2 O+H2 +N2 CH4 +2NiO↔2Ni+2H2 +CO2 • Massflowrate H2 +NiO↔Ni+H2 O CO+NiO↔Ni+CO2 CH4 +NiO↔Ni+2H2 +CO 𝐺< = H !" CH4 +H2 O↔3H2 +CO !" CH4 +CO2 ↔2H2 +2CO !" CO+H2 O↔H2 +CO2 𝐺S = 𝛽 ' 𝜌: ' 1 − 𝜀8Q ' 𝑈" → 𝐺< ≥ 𝐺S 𝐺U = 𝑈1 ⁄ℎ " ' 𝑚" ⁄𝐴" → 𝐺< < 𝐺S !" CH4 +N" ↔Ni-C+2H2 !" C+H2 O↔H2 +CO • Pressuredrop !" C+CO2 ↔2CO CH4 +H2 O+N2 ∆𝑃" = 𝜌: ' 1 − 𝜀2 ' 𝑔 ' ℎ 2 + 2Ni+O2 →2NiO AIR 𝑔 ' 𝑊" ' ℎ" − ℎ2 𝐴" ' 𝑈1 FluidizationXV– May22-27,2016 Cyclone DEPLETED AIR hp: Collection efficiency was assumed to be 1. • Pressuredrop ∆𝑃?V? = 𝜌Q ' 𝐾? ' 𝑈? CH4 +CO+CO2 +H2 O+H2 +N2 CH4 +2NiO↔2Ni+2H2 +CO2 H2 +NiO↔Ni+H2 O CO+NiO↔Ni+CO2 CH4 +NiO↔Ni+2H2 +CO !" CH4 +H2 O↔3H2 +CO !" CH4 +CO2 ↔2H2 +2CO !" CO+H2 O↔H2 +CO2 !" CH4 +N" ↔Ni-C+2H2 !" C+H2 O↔H2 +CO !" C+CO2 ↔2CO CH4 +H2 O+N2 2Ni+O2 →2NiO AIR FluidizationXV– May22-27,2016 Downcomer/L-Valve DEPLETED AIR • Pressuredrop ∆𝑃2XS = 𝐾4 ' 𝑢Q[ − 𝑢<[ 𝐻 − 𝐿Y ∆𝑃04 = 𝐾A ' 𝑢Q\ − 𝑢<\ 𝐿A 0.0649 ' 𝜌: a.bbc ' 𝐿A 𝑊1 ∆𝑃04 = 𝐷04 a.efg ' 𝑑: a.hif 𝐴" CH4 +CO+CO2 +H2 O+H2 +N2 CH4 +2NiO↔2Ni+2H2 +CO2 H2 +NiO↔Ni+H2 O CO+NiO↔Ni+CO2 CH4 +NiO↔Ni+2H2 +CO a.jfk !" CH4 +H2 O↔3H2 +CO • Aerationgasflowrate 𝑄04 = 𝑄A + 𝑄4 !" CH4 +CO2 ↔2H2 +2CO !" CO+H2 O↔H2 +CO2 !" CH4 +N" ↔Ni-C+2H2 !" C+H2 O↔H2 +CO !" C+CO2 ↔2CO CH4 +H2 O+N2 2Ni+O2 →2NiO AIR FluidizationXV– May22-27,2016 ΔH0, kJ/mol R1)2𝑁𝑖 + 𝑂h → 2𝑁𝑖𝑂 R2)𝐶𝐻g + 2𝑁𝑖𝑂 ↔ 2𝑁𝑖 + 2𝐻h + 𝐶𝑂h R3)𝐻h + 𝑁𝑖𝑂 ↔ 𝑁𝑖 + 𝐻h 𝑂 -479 161 -2 q* 206 q* 247 R6)𝐶𝐻g + 𝐻h 𝑂 ↔ 3𝐻h + 𝐶𝑂 R7)𝐶𝐻g + 𝐶𝑂h ↔ 2𝐻h + 2𝐶𝑂 q* R8)𝐶𝑂 + 𝐻h 𝑂 ↔ 𝐻h + 𝐶𝑂h q* R4)𝐶𝑂 + 𝑁𝑖𝑂 ↔ 𝑁𝑖 + 𝐶𝑂h -43 R9)𝐶𝐻g + 𝑁𝑖 ↔ 𝑁𝑖 − 𝐶 + 2𝐻h R5)𝐶𝐻g + 𝑁𝑖𝑂 ↔ 𝑁𝑖 + 2𝐻h + 𝐶𝑂 203 R10)𝐶 + 𝐻h 𝑂 ↔ 𝐻h + 𝐶𝑂 • • • • • OxygenCarrier:15wt.%Ni/𝛾-Al2O3 Efficiencyofairpre-heater:90% CH4:H2Ois3:1 FRisisothermal ARisadiabatic -41 74 q* 131 q* 172 R11))𝐶 + 𝐶𝑂h ↔ 2𝐶𝑂 C. Dueso et al., Chem. Eng. J. 188 (2012) 142-154 I. Iliuta et al., AIChE J. 56 4 (2010) 1063–1079 F. Bustamante et al., AIChE J. 50 (2004) 1028–1041 F. Bustamante et al., AIChE J. 51 (2005) 1440– 1454 FluidizationXV– May22-27,2016 Mass Balances Parameters Dense regime/phase Operating conditions T fuel [ K ] P [ Pa] minv [kg ] U B [m ⋅ s −1 ] U R [m ⋅ s −1 ] Q LV [m3 ⋅ s −1 ] U LS [m ⋅ s −1 ] 𝑄u,*+ ' 𝐶v,*+ − 𝑄u,wxy ' 𝐶v,u + 𝑚<>,u ' ∑* 𝑟* ' 𝛼v =0 𝑊u,*+ ' 𝐶<>,*+ − 𝑊u ,wxy ' 𝐶<>,u + 𝑀<> ' 𝑚<>,u ' ∑* 𝑟* ' 𝛼v =0 Properties of bed materials 300 ρ p [kg ⋅ m −3 ] 5 10 d p [ m] 11.6 ε mf [−] 0.5 ε D [ −] 2.7 ε [ −] −5 B 5.5 ⋅10 εV [−] ε H [ −] 2U mf 2540 2.55 ⋅10−4 0.445 0.445 0.445 0.423 0.488 GEOMETRICAL CHARACTERISTICS Diluted regime/Free Board 1 𝑑𝑛v,u = • 𝑟* ' 𝛼v 𝐴u 𝑑ℎ u * Riser DR [m] hR [m] BFB DB [m] hB [m] Downcomer DD [m] LV [m] 0.102 5.6 0.12 2 0.04 3.6 L-valve DLV [m] LH [m] LE [m] Cyclone K C [ −] Loop-Seal Asc [m 2 ] hrc [m] 0.04 0.4 0.4 78 0.0025 0.2 Energy balances 𝑊u,*+ ' ∑<> 1⁄𝑀<> ' 𝐶<>,*+ ' ℎ <>,*+ − 𝑊u,wxy ' ∑<> 1⁄ 𝑀<> ' 𝐶<>,u ' ℎ <>,u + 𝑄u,*+ ' ∑v 𝐶v,*+ ' ℎv,*+ − 𝑄u,wxy ' "* ∑v 𝐶v,u ' ℎv,u + ∑* ∆𝐻"* ' 𝑛v,u =0 FluidizationXV– May22-27,2016 Fuel Reactor:effect ofheight ofthe BFBweir ℎ- ↑≫ 𝑚-.- ↑ 𝑎𝑛𝑑𝐺< ↓ so 𝜏-.- ↑ 𝑎𝑛𝑑𝑂2 ↓ WGSreactionratedecreaseswithT FluidizationXV– May22-27,2016 Fuel Reactor:effect ofsolid circulation rate 𝐺< ↑≫ 𝑁𝑖𝑂: 𝐶𝐻4 ↑ so 𝜂?A† ↑ 𝑎𝑛𝑑𝜂A‡ ↓ 𝐻h + 𝑁𝑖𝑂 ↔ 𝑁𝑖 + 𝐻h 𝑂 FluidizationXV– May22-27,2016 AirReactor:effect ofinlet airpre-heat exchanger Withoutpre-heatexchangerthe temperatureofinletairistoolowto driveNioxidationreaction FluidizationXV– May22-27,2016 A simple tool to evaluate the performance of a CLR process carried out in a DIFB was developed. The model is able to predict both main hydrodynamic variables and CLR performances. Higher H2 production can be achieved reducing the amount of oxygen available in the FR decreasing solid circulation rate. If no air pre-heating is used, the temperature of air at the inlet of AR is too low to drive Ni oxidation reaction. FluidizationXV– May22-27,2016
