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    EUROKIN SPREADSHEET FOR ASSESSMENT OF TRANSPORT LIMITATIONS IN GAS-SOLID FIXED BEDS
    		This webtool is a spreadsheet for selecting proper conditions in a gas-solid fixed-bed reactor for intrinsic reaction kinetics.
    		It was developed by the Eurokin consortium (http://www.eurokin.org) and made accessible to the public for free in 2012.
    		It consists of this spreadsheet and a document with background informationEUROKIN_fixed-bed_html_guide.pdf.
    		It requires the physical properties of the components and calculates the heat- and mass transfer coefficients according to correlations from literature.
    		The obtained values are substituted into several criteria which indicate if the resistance becomes limiting.
    		The red numbers within brackets refer to the corresponding section in the background document 'EUROKIN_fixed-bed_html_guide'.
    		The blue numbers should be inserted by the user; the current values correspond to an example on N2O decomposition.
    		Disclaimer: This spreadsheet and its functionality have not been tested exhaustively and represent a beta-version. The use of the spreadsheet
    		is at the user’s own risk. Under no circumstances, the Eurokin consortium will be liable for any damages (including, without limitation, conse-
    		quential, incidental or special damages, including lost profits or lost savings), or for illegal acts or actions, arising from the use of the spreadsheet.
    		Also the copyright holders expressly excludes liability for consequential loss or damage which may arise in respect of this spreadsheet,
    		its use, the system or in respect of other equipment or property for loss of profit, business revenue, goodwill or anticipated savings.
    		Regardless of whether any remedy fails of its essential purpose, in no event will the copyright holders be liable for incidental, indirect,
    		special or consequential damages, notwithstanding being aware of the possibility of such damages.
    		Print button: Push the print button for printing; this webpage is printer-friendly on A4 paper (4 pages) when choosing landscape format.
    		Reset button: Push the reset button to get back all the default values (the buttons are located at the bottom).
    		 
      Input                  
    Reaction (1)
    Mol. weight
    		Diffus. volume
    		Feed composition (mol %) Name [mol-%]
    		stoichiometry [kg/mol]
    [m3/mol] (15)
    Limiting reactant (= "A")
    (1)
    Second compound
    Third compound
    Dilution (or 4th compound)
    		Mixture value :
    		Reaction conditions:
    Catalyst temperature
    		[K]
    (1)
    		Calculated values
    Total pressure
    		[kPa]
    Volumetric flow at reaction cond.
    		[m3/s]
    Total molar inlet flow
    		[mol/s]
    Volumetric flow at STP
    		[ml/min]
    Superficial velocity
    		[m/s]
    		Properties of catalyst and dilution
    Particle Reynolds number
    Amount of catalyst
    		[g]
    Density mixture
    		[kg/m3]
    Amount of bed dilution
    		[g]
    Molar volume
    		[m3/mol]
    Catalyst pellet diameter
    		[mm]
    Pr
    		[-]
     
    Bed porosity
    		[m3/m3bed]
    (2)
    		 
    Sc
    		[-]    
     
    Cat. internal specific area
    		[m2/g]    
    Space time [Wcat/(mol-A/s)]
    		[kg/s mol]    
     
    Catalyst pellet porosity
    		[m3/m3pellet]    
    Weight dilution degree
    		[kgdil/(kgcat+kgdil)]  
     
    Catalyst bulk density
    		[kg/m3bed]    
    Volume dilution degree
    		[m3dil/(m3cat+m3dil)]  
    Catalyst pellet tortuosity
    		[-]
    Bed cross-sectional area
    		[mm2]
    Cat. pellet thermal conduct.
    		[W/mK]
    Bed height
    		[mm]
     
    Dilution pellet density
    		[kg/m3pellet]    
    Real residence time in bed
    		[s]    
    Dil. pellet thermal conductivity
    		[W/mK]
    Total catalyst bed volume
    		[mm3]
    Catalyst pellet density
    		[kg/m3]
    		Reactor dimensions:
    Internal reactor diameter
    		[mm]
    Average pore radius
    		[nm]
    Diameter thermowell
    		[mm]
    Catalyst solid density
    		[kg/m3]
    Catalyst pore volume
    		[ml/g]
    		Reaction rate
    Average pellets thermal cond.
    		[W/m K]
    Observed reaction rate
    		[mol-A/kg-cat.s]
    (1)
    Reaction order A
    		[-]
    Observed rate constant
    		[mol-A/kg-cat.s.Pa-An]
     
    Apparent activation energy
    		[kJ/mol-A]    
    Reaction rate per pellet volume
    		[mol-A/mpellet3 s]  
    Reaction enthalpy
    		[kJ/mol-A]
    Conversion of A
    (3)
    		 
      Physical properties of the components            
    		General physical properties (mixture values)
    		Calculation of Diffusion coefficient
    (15)
    		Heat capacity [J/mol K]
    		[m2/s]
    		Viscosity [kg/m s]
    		[m2/s]
    		Thermal conductivity [W/m K]
    		[m2/s]
    		(The user should adapt these values accordingly)
    		[m2/s]
    		[m2/s]
    		[m2/s]
    		[m2/s]
    		 
      Results concerning transport limitations and other disturbing phenomena      
    		Pressure drop over the catalyst bed
    (4)
    		Conditions for allowing assumption ideal plug flow behaviour
    		Friction factor
    		Axial dispersion
    (5)
      Pressure drop over the bed [Pa]     Bo (=Pep) [-]    
    		DP/P ratio ; must be < (0.2/n) =
    Constant in criterion
              hbed /dp (minimum required)      
                  hbed /dp (experimental)      
    		Conditions for the maximum bed dilution
    (7)
    		Relative deviation (D)
    		Maximum allowed b [vol-dil/vol-tot]
    		Radial dispersion
    (6)
      Experimental b      
    Criterion: dt /dp should be at least
    		     
              dt /dp      
    		External mass transport limitation
    (8)
    		Sh [-]
    		Internal diffusion limitation
    (9)
      Mass transfer coefficient (kg) [m3/m2s]     [m2/s]    
     
    av = 6/dp
    		[m2/m3-pellet]     Weisz modulus (F) ; must be <  
    		[mol/m3]
    		Approximate Thiele modulus (f) [-]
    		Ca ; must be < 0.05/n
    		tanh (3f) [-]
    Efficiency (for n = 1)
    		[-]
    		Approximated efficiency (h) [-]
    		Radial heat transfer limitation
    (11)
      Perf [-]     External heat transport limitation
    (10)
    		 
      ler,0/lG [-]       Nu [-]    
      ler,conv/lG       Note that Nu may get as low as 0.1 at Re <1 in case of channeling !  
      ler [W/mK]     Heat transfer coefficient ap = hw [W/m2 K]    
    		Pr (air, 80oC)
    		| DT(film) | [K]; must be <
      aw,0 [W/m2 K]            
      aw,conv [W/m2 K]                
      aw [W/m2 K]     Temperature gradient within the pellet
    (12)
    		 
    		| DT(rad) | [K]; must be <
    		The effect of the internal temperature gradient on the net
    		production rate is smaller than 5% if :
    		If the temperature of the wall is measured instead of the tem-
    (11)
    		| DT(int) | [K]; must be <
    		perature at the central bed axis, another criterion applies:
    | DT(rad) |
    		[K]; must be <
     
    Biwall
    		[-]     Adiabatic temperature rise (DTad)
    (13) (14)
    		 
    		DT(ad) [K]
     
       
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