modelSteamReformer_NaturalGas_to_H2
SteamReformer with calculation of reaction kinetics depending on input gascomposition, including mass fraction balance and reaction volume (input natural gas, output H2 rich syngas)
Extends from TransiEnt.Basics.Icons.Model (Icon for models).
Information
1. Purpose of model
Steam Reformer with calculation of reaction kinetics depending on input gas composition, including mass fraction balance and reaction volume (input natural gas, output H2 rich syngas).
2. Level of detail, physical effects considered, and physical insight
(no remarks)
3. Limits of validity
(no remarks)
4. Interfaces
TransiEnt.Basics.Interfaces.Gas.IdealGasTempPortIn feed(Medium=Syngas)
TransiEnt.Basics.Interfaces.Gas.IdealGasTempPortOut drain(Medium=Syngas)
Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a heatport
5. Nomenclature
(no remarks)
6. Governing Equations
(no remarks)
7. Remarks for Usage
(no remarks)
8. Validation
Validation has been done as part of the master thesis [1]
9. References
[1] Modellierung und Simulation von erdgasbetriebenen Brennstoffzellen-Blockheizkraftwerken zur Heimenergieversorgung
Master thesis, Simon Weilbach (2014)
10. Version History
Model created by Simon Weilbach (simon.weilbach@tuhh.de) on 01.10.2014
Model revised by Pascal Dubucq (dubucq@tuhh.de) on 01.10.2015
Quality check (Code conventions) by Rebekka Denninger on 01.10.2016
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.Pressure | p_reformer | 1.013e5 | Pressure in the reformer |
| Modelica.Units.SI.Density | d_kat | 1900 | Density of catalyst |
| Real | scale_kat | 1 | Influencing factor of the reaction heat under the assumption that more reactions occur than through concentration changes observed |
| Real | eps | 1e-6 | Accuracy of the calculation |
| Modelica.Units.SI.Volume | V_reac | 0.001 | Volume of the reactor |
| Real | eps_kat | 0.4 | Porosity of the catalyst |
| Real[4] | K_oi | {6.65e-4, 8.23e-5, 6.12e-9, 1.77e5} | Adsorption coefficient constant of the component i {CH4, CO, H2, H2O} |
| Real[4] | dH_i | {-38280, -70650, -82900, 88680} | Vector with the enthalpies of the component i {CH4, CO, H2, H2O} |
| Real[2] | K_oiC | {1.26e-1, 7.78e-7} | Adsorption coefficient constant of the combusted component i {CH4-c, O2-c} |
| Real[2] | dH_iC | {-27300, -92800} | Vector with the enthalpies of the combusted component i {CH4-c, O2-c} |
| Real[5] | k_oi | {1.17e15, 2.83e14, 5.43e5, 8.11e5, 6.82e5} | k_oi |
| Real[5] | E_j | {240100, 243900, 67130, 86000, 86000} | Activation energy |
| Real[4] | Delta_H_R | {206.2*1000, 164.9*1000, -41.1*1000, -802.7*1000} | Reaction heat of the reactions 1 to 4 in J/mol |
| TransiEnt.Basics.Media.Gases.Gas_VDIWA_SG7_var | Syngas | TransiEnt.Basics.Media.Gases.Gas_VDIWA_SG7_var() | Medium model of Syngas |
| Modelica.Units.SI.SpecificHeatCapacity | cp | 850 | |
| Modelica.Units.SI.Mass | m | V_reac*d_kat*(1 - eps_kat) | |
| Modelica.Units.SI.Temperature | T_reformer_min | 500 + 273.15 |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| TransiEnt.Basics.Interfaces.Gas.IdealGasTempPortIn | feed | ||
| TransiEnt.Basics.Interfaces.Gas.IdealGasTempPortOut | drain | ||
| Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a | heatport |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| TransiEnt.SimCenter | simCenter | ||
| Real[5] | k_i | Reaction coefficient of the reaction i | |
| Real | K_I | exp(-26830/T_reformer + 30.114) | Equilibrium constant of the first equation in [bar] |
| Real | K_III | exp(4400/T_reformer - 4.036) | Equilibrium constant of the third equation in [-] |
| Real | K_II | K_I*K_III | Equilibrium constant of the second equation in [bar] |
| Real[6] | r_i | Reaction rate of the components {CH4, O2, CO2, H2O, H2, CO} | |
| Real[6,4] | A | [-1, -1, 0, -1; 0, 0, 0, -2; 0, 1, 1, 1; -1, -2, -1, 2; 3, 4, 1, 0; 1, 0, -1, 0] | Matrix for calculating the reaction rates |
| Real[4] | b_running | {0.07*R1, 0.06*R2, 0.7*R3, 0.05*R4} | |
| Real[4] | b_preheat | {0, 0, 0, 0} | |
| Real[4] | b | ||
| Real[2] | K_iC | Adsorption coefficient constant of the combusted component i {CH4-c, O2-c} | |
| Real | OMEGA | Term in the reaction rate equations | |
| Real | R1 | Reaction rate 1 | |
| Real | R2 | Reaction rate 2 | |
| Real | R3 | Reaction rate 3 | |
| Real | R4 | Reaction rate 4 | |
| Real[4] | K_i | Adsorption coefficient constant of the component i {CH4, CO, H2, H2O} | |
| Real[7] | x_i | Mole fraction of the gas mixture in the reformer during the reaction | |
| Modelica.Units.SI.MassFraction | xi_ch4 | Mass fraction CH4 | |
| Modelica.Units.SI.MassFraction | xi_o2 | Mass fraction O2 | |
| Modelica.Units.SI.MassFraction | xi_co2 | Mass fraction CO2 | |
| Modelica.Units.SI.MassFraction | xi_h2o | Mass fraction H2O | |
| Modelica.Units.SI.MassFraction | xi_h2 | Mass fraction H2 | |
| Modelica.Units.SI.MassFraction | xi_co | Mass fraction CO | |
| Modelica.Units.SI.MoleFraction | x_n2 | Mole fraction N2 | |
| Modelica.Units.SI.Pressure | p_ch4 | sg.p_i[1]/1e5 | Mass fraction CH4 |
| Modelica.Units.SI.Pressure | p_o2 | sg.p_i[2]/1e5 | Mass fraction 02 |
| Modelica.Units.SI.Pressure | p_co2 | sg.p_i[3]/1e5 | Mass fraction CO2 |
| Modelica.Units.SI.Pressure | p_h2o | sg.p_i[4]/1e5 | Mass fraction H2O |
| Modelica.Units.SI.Pressure | p_h2 | sg.p_i[5]/1e5 | Mass fraction H2 |
| Modelica.Units.SI.Pressure | p_co | sg.p_i[6]/1e5 | Mass fraction CO |
| Real | m_ges | ||
| Modelica.Units.SI.Temperature | T_reformer | Temperature of the reformer section | |
| Modelica.Units.SI.Temperature | T_gas | (T_reformer + START.T)/2 | Assumption of the average temperature between reformer temperature and inlet temperature |
| Modelica.Units.SI.MassFlowRate | m_flow | feed.m_flow | Mass flow rate of the gas mixture through the reformer |
| SI.HeatFlowRate | Q_flow_reac | Heat flow due to reactions | |
| TILMedia.Gas_pT | sg | ||
| TILMedia.Gas_pT | START |