Dear David,
Thank you for the contact with Vincent Post. He helps me to use
"USER_GRAPH" in an easy way. There were a synthatic problem concerning the
outpout of pe (30 GRAPH_SY -LA("e-") was to be tape).
Now I couldn't progress in modelling uranium-rollfront. The idea was to
create a redox front such that inflooding U(VI) will precipitate at it.
What I've yet done is to reduce to pe and uranium concentration trough
sucessive equilibria with selected uranium phases. Although these are
relevant for similating real life, it was not the aim (not a "real front").
I've found in the literature (Merkel & Planer-Friedrich: Abbau_10000Tage;)
an example where the degradation of organic carbon induces the
pricipitation of soluble uranium. but incooporate this kinetic step in the
transport could not produces the same result (Roll-front122;). What is your
comment?
Thank you for the answer, I'll be absent for the rest of the week.
Have a nice time,
ChicgouaTITLE Abbau organischer Substanz im Grundwasserleiter unter Reduktion redoxsensitiver Elemente (Fe, As, U, Cu, Mn, S) (10000 Tage)
SOLUTION 1 Leaching-Lösung
units ppm
pe 4 O2(g) -0.7
temp 10
pH 2.3
S(6) 5000 as SO4 charge
Cl 450
F 1
N(5) 100 as NO3
U 40
Fe 600
Zn 100
As 2
Mn 20
Pb 0.2
Ni 5
Cu 3
C 1 # ergänzt wegen calcite
Cd 1
Li 0.1
Na 500
K 4
Mg 50
Ca 400
Al 200
Si 50
save solution 1
end
use solution 1
KINETICS 1
Calcite
-tol 1e-8
-m0 1e-2
-m 1e-2
-parms 50 0.6
Organic_C
-formula CH2O
-tol 1e-8
-m0 1 # mol/kgw
-m 1
-steps 864000000 in 100 steps # 10.000 Tage
-step_divide 1000000
Pyrite
-tol 1e-8
-m0 1
-m 1
-parms -5.0 0.1 .5 -0.11
RATES
Calcite
-start
1 rem parm(1) = A/V, 1/dm parm(2) = exponent for m/m0
5 if time > 8640000 then goto 200
10 si_cc = si("Calcite")
20 if (m <= 0 and si_cc < 0) then goto 200
30 k1 = 10^(0.198 - 444.0 / (273.16 + tc) )
40 k2 = 10^(2.84 - 2177.0 / (273.16 + tc) )
50 if tc <= 25 then k3 = 10^(-5.86 - 317.0 / (273.16 + tc) )
60 if tc > 25 then k3 = 10^(-1.1 - 1737.0 / (273.16 + tc) )
70 t = 1
80 if m0 > 0 then t = m/m0
90 if t = 0 then t = 1
100 moles = parm(1) * 0.1 * (t)^parm(2)
110 moles = moles * (k1 * act("H+") + k2 * act("CO2") + k3 * act("H2O"))
120 moles = moles * (1 - 10^(2/3*si_cc))
130 moles = moles * time
140 if (moles > m) then moles = m
150 if (moles >= 0) then goto 200
160 temp = tot("Ca")
170 mc = tot("C(4)")
180 if mc < temp then temp = mc
190 if -moles > temp then moles = -temp
200 save moles
-end
Organic_C
-start
10 if (m <= 0) then goto 200
20 mO2 = mol("O2")
30 mNO3 = tot("N(5)")
40 mSO4 = tot("S(6)")
# 50 rate = 1.57e-9*mO2/(2.94e-4 + mO2) + 1.67e-11*mNO3/(1.55e-4 + mNO3)
50 rate = 1.57e-7*mO2/(2.94e-4 + mO2)
# 60 rate = rate + 1.e-13*mSO4/(1.e-4 + mSO4)
60 rate = rate + 1.e-10*mSO4/(1.e-4 + mSO4)
70 moles = rate * m * (m/m0) * time
80 if (moles > m) then moles = m
200 save moles
-end
Pyrite
-start
1 rem parm(1) = log10(A/V, 1/dm) parm(2) = exp for (m/m0)
2 rem parm(3) = exp for O2 parm(4) = exp for H+
10 if (m <= 0) then goto 200
20 if (si("Pyrite") >= 0) then goto 200
20 rate = -10.19 + parm(1) + parm(3)*lm("O2") + parm(4)*lm("H+") + parm(2)*log10(m/m0)
30 moles = 10^rate * time
40 if (moles > m) then moles = m
50 if (moles >= (mol("O2")/3.5)) then moles = mol("O2")/3.5
200 save moles
-end
EQUILIBRIUM_PHASES
Al(OH)3(a) 0 0
Calcite 0 0
Coffinite 0 0
Jurbanite 0 0
Kaolinite 0 0
Pyrite 0 0
Uraninite(c) 0 0
SELECTED_OUTPUT
-file Abbau_10000Tage.csv
-totals Fe(2) Fe(3) U(6) As(3) As(5) Cu(1) Cu(2) Mn(2) Mn(3) Mn(6) Mn(7)
-molalities SO4-2 CaSO4 UO2+2 UO2SO4 CuCl2- Cu+ CuCl3-2 CuHCO3+ Cu+2 CuSO4 CuCO3
-saturation_indices Al(OH)3(a) Calcite Coffinite Jurbanite Kaolinite Pyrite Uraninite(c)
-kinetic_reactants Organic_C Pyrite Calcite
-pH true
-pe true
END
TITLE Rollfront
SOLUTION 0 Rainwater
units mmol/kgw
temp 25.0
pH 7.0 charge
pe 4.0
EQUILIBRIUM_PHASES 0
CO2(g) -3 10
O2(g) -0.7 10
Save Solution 0
END
SOLUTION 12-21
SOLUTION 1-10
USE solution 0
EQUILIBRIUM_PHASES 1-2
Calcite 0.0 0.1
Goethite 0.0 0.1
SAVE solution 1-2
END
USE solution 1
EQUILIBRIUM_PHASES 3
Schoepite 0.0 0.1
Calcite 0.0 0.1
Goethite 0.0 0.1
SAVE solution 3
END
USE solution 3
EQUILIBRIUM_PHASES 4-7
Schoepite 0.0 0.1
Calcite 0.0 0.1
Pyrite 0.0 0.1
SAVE solution 4
END
USE solution 4
KINETICS 7-10
Organic_C
-formula CH2O
-tol 1e-8
-m0 1
-m 1
-steps 51840000 in 100 steps
RATES
Organic_C
-start
10 if (m <= 0) then goto 200
20 mO2 = mol("O2")
30 mNO3 = tot("N(5)")
40 mSO4 = tot("S(6)")
50 rate = 1.57e-7*mO2/(2.94e-4 + mO2)
60 rate = rate + 1.e-10*mSO4/(1.e-4 + mSO4)
70 moles = rate * m * (m/m0) * time
80 if (moles > m) then moles = m
200 save moles
-end
END
KNOBS
-pe 2
-step 2
-iterations 200
SOLUTION_SPECIES
H2O + .01e- = H2O-0.01
log_k -9
TRANSPORT
-cells 10
-shifts 100
-time_step 86400
-flow_direction forward
-length 1
-dispersivities 2.0
-punch_cells 1-10
-punch_frequency 100
-stagnant 1 1.056e-10 0.05 0.15
-print_cells 1-10
-print_frequency 100
PRINT
-reset false
SELECTED_OUTPUT
-file Roll-front122.csv
-reset false
-time false
-distance true
-totals U
-pH true
-pe true
USER_GRAPH
-headings x U pe
-chart_title Uranrollfront
-axis_titles "Distance[m]" "Konzentration [Mol]" "pe-Wert"
-axis_scale y_axis 0.6 30
-axis_scale secondary_y_axis -6.0 12.0
-initial_solutions false
-plot_concentration_vs x
10 GRAPH_X DIST
20 GRAPH_Y tot("U")
30 GRAPH_SY -LA("e-")
ENDPlease note that some U.S. Geological Survey (USGS) information accessed through this page may be preliminary in nature and presented prior to final review and approval by the Director of the USGS. This information is provided with the understanding that it is not guaranteed to be correct or complete and conclusions drawn from such information are the sole responsibility of the user.
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Email:dlpark@usgs.gov
Last modified: $Date: 2005-09-13 21:04:21 -0600 (Tue, 13 Sep 2005) $
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