CHEMP
CHEMP provides data for calculating the thermophysical properties of the NAPL/chemical. The units of many of these constants are not standard metric units, and care must be taken to ensure that the appropriate units are used. Most of the data used in this block can be taken from Appendix A of Reid et al. (1987), where the same units are used as here.
Record CHEMP.1
Free format, or Format(I5)
NumHyC
NumHyC number of organic chemicals/hydrocarbons for which data are to be entered. NumHyC must be <19.
Record CHEMP.2
Free format, or Format(A20, 8I5)
HcNames, RecordID(8)
HcNames name of the organic chemical.
RecordID a list of the data record IDs. Only the records listed here will be read. As many as 8 IDs can be listed. The ID must be in the range of 3-10 corresponding to the following data records, No additional data record will be read if it is neglected. Most data records are not required or have been provided internally for the ECOF module. (For ECOF module only)
Record CHEMP.3
Free format for 5 parameters, or Format (5E10.4)
TCRITM, PCRITM, ZCRITM, OMEGAM, DIPOLMM
TCRITM chemical critical temperature, K.
PCRITM chemical critical pressure, bar (1 bar = Pa).
ZCRITM chemical critical compressibility.
OMEGAM Pitzer's acentric factor for the chemical.
DIPOLMM chemical dipole moment, debyes.
Record CHEMP.4
Free format for 5 parameters, or Format (5E10.4)
TBOILM, VPAM, VPBM, VPCM, VPDM
TBOILM chemical normal boiling point, K.
VPAM chemical vapor pressure constant from Reid et al. (1987). If VPAM ≠ 0 use Wagner correlation (Reid et al., 1987), for VPAM = 0 use Antoine Correlation.
VPBM chemical vapor pressure constant from Reid et al. (1987).
VPCM chemical vapor pressure constant from Reid et al. (1987).
VPDM chemical vapor pressure constant from Reid et al. (1987).
Record CHEMP.5
Free format for 5 parameters, or Format (5E10.4)
AMWTM, CPAM, CPBM, CPCM, CPDDM
AMWTM chemical molecular weight, g/mole.
CPAM chemical ideal gas heat capacity constant from Reid et al. (1987).
CPBM chemical ideal gas heat capacity constant from Reid et al. (1987)
CPCM chemical ideal gas heat capacity constant from Reid et al. (1987)
CPDDM chemical ideal gas heat capacity constant from Reid et al. (1987)
Record CHEMP.6
Free format for 5 parameters, or Format (5E10.4)
RHOREFM, TDENREF, DIFV0M, TDIFREF, TEXPOM
RHOREFM reference NAPL (liquid) density, kg/m3.
TDENREF reference temperature for NAPL density, K.
DIFV0M reference binary diffusivity of VOC in air, m2/s.
TDIFREF reference temperature for gas diffusivity, K.
TEXPOM exponent for calculation of chemical diffusivity.
Record CHEMP.7
Free format for 5 parameters, or Format (5E10.4)
VLOAM, VLOBM, VLOCM, VLODM, VOLCRITM
Two options are available for calculating the NAPL liquid viscosity. The liquid viscosity constants VLOAM - VLODM for the desired NAPL may be assigned data given in Table 9-8 of Reid et al. (1987), and the viscosity will be calculated using a polynomial fit to actual viscosity data (Eq. 4.3.11 in TMVOC user manual). Alternatively, VLOAM and VLOBM may be set equal to 0, and VLOCM and VLODM are assigned equal to a reference viscosity and a reference temperature, respectively. In this case, the viscosity is calculated from a more general (and less accurate) empirical correlation (Van Velzen et al., 1972).
VLOAM liquid NAPL viscosity constant from Reid et al. (1987).
VLOBM liquid NAPI viscosity constant from Reid et al. (1987).
VLOCM liquid NAPL viscosity constant from Reid et al. (1987). If VLOAM and VLOBM = 0, VLOCM is reference NAPL viscosity in units of cP (1 cP = 10-3 Pa-s).
VLODM liquid NAPL viscosity constant from Reid et al. (1987). If VLOAM and VLOBM = 0, VLODM is reference temperature for NAPL viscosity in units of Kelvin.
VOLCRITM chemical critical volume, cm3/mole.
Record CHEMP.8
Free format for 4 parameters, or Format (4E10.4)
SOLAM, SOLBM, SOLCM, SOLDM
The chemical solubility is calculated from the polynomial SOLUBILITY = SOLAM + SOLBM*T + SOLCM* + SOLDM* . If data for the solubility as a function of temperature are available, then SOLAM, SOLBM, SOLCM, and SOLDM should be calculated from a polynomial fit of the data. If such data are not available (the usual case), the solubility will be assumed to be constant, and SOLAM should be set equal to the known solubility, with SOLBM, SOLCM, and SOLDM set equal to 0.
SOLAM constant for chemical solubility in water, mole fraction.
SOLBM constant for chemical solubility in water, mole fraction/.
SOLCM constant for chemical solubility in water, mole fraction/.
SOLDM constant for chemical solubility in water, mole fraction/.
Record CHEMP.9
Free format for 3 parameters, or Format (3E10.4)
OCKM, FOXM, ALAMM
OCKM chemical organic carbon partition coefficient Koc (see Eq. 4.4.2 in TMVOC user manual), m3/kg.
FOCM default value for fraction of organic carbon in soil, used for all domains for which no specific value is provided in record ROCKS.1.1.
ALAMM decay constant for biodegradation of VOC, s-1. Biodegradation is assumed to take place only in the aqueous phase, and to follow a first order decay law, MVOC(t) = MVOC,0 * exp (-λ t). The decay constant λ = ALAMM is expressed in terms of the half life T1/2 of the VOC as follows: λ = (ln 2) / T1/2. Default is ALAMM = 0.
Record CHEMP.10 (for ECOF module only)
Free format for 20 parameters, or Format (20E10.4)
bij(20)
bij a list of user-specified binary interaction coefficients for current component, the number of the inputted coefficients must be equal to the total hydrocarbon component number NumHyC+1 and in the order consistent with the components defined under this keyword (CHEMP) with additional coefficient at the end for water.
Repeat records CHEMP.2 through CHEMP.10 for a total of NumHyC (up to eighteen) different organic chemicals.
Used in: TMVOC, ECOF
EXAMPLE 1:
CHEMP
2 //Number of organic chemicals
BENZENE // Name of the first chemical
562.2, 48.2, 0.271, 0.212, 0.0 //CHEMP.3 for BENZENE
353.2, -6.98273, 1.33213, -2.62863, -3.33399 //CHEMP.4 for BENZENE
78.114, -.3392E+02, 0.4739E+00, -.3017E-03, 0.7130E-07 //CHEMP.5 for BENZENE
885., 289.00, 0.770E-05, 273.10, 1.52 //CHEMP.6 for BENZENE
0.4612E+01, 0.1489E+03, -.2544E-01, 0.2222E-04, 259.0 //CHEMP.7 for BENZENE
0.411E-03, 0.000E+00, 0.000E+00, 0.000E+00 //CHEMP.8 for BENZENE
0.891E-01, 0.001, 0.0 //CHEMP.9 for BENZENE
n-DECANE // Name of the second chemical
617.700, 21.200, 0.249, 0.489, 0.00 //CHEMP.4 for n-DECANE
447.300, -8.56523, 1.97756, -5.81971, -0.29982 //CHEMP.4 for n-DECANE
142.286, -7.913E+0, 9.609E-1, -5.288E-4, 1.131E-7 //CHEMP.5 for n-DECANE
730.000, 293.000, 1.000E-5, 293.000, 1.600 //CHEMP.6 for n-DECANE
0.0, 0.0, 0.5900, 293.000, 603.000 //CHEMP.7 for n-DECANE
3.799e-7 //CHEMP.8 for n-DECANE, constant solubility
0.000 //CHEMP.9 for n-DECANE. The first parameter is 0.0, others set to default values.
EXAMPLE 2 (for ECOF):
CHEMP
3 //Number of hydrocarbon components
CO2, 10 // Name of the first component, will read data record 10 (bij) only.
0.0, 0.086292, 0.097866* // bij between CO2 and CO2, C4H10, C10H22 , respectively.
C4H10,10
8.6292E-02, 0.0, 3.3693E-08 // bij between C4H10 and CO2, C4H10, C10H22 , respectively
C10H22,10
9.7866E-02, 3.3693E-08, 0.0 // bij between C10H22 and CO2, C4H10, C10H22 , respectively
*The coefficients between water and and these components (the 4th slot) do not present in the input. The default values will be used.
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