RATES Calcite-start 1 REM PARM(1) = specific surface area of calcite, cm^2/mol calcite 2 REM PARM(2) = exponent for M/M0 10 si_cc = SI("Calcite") 20 IF (M <= 0 and si_cc < 0) THEN GOTO 200 30 k1 = 10^(0.198 - 444.0 / TK ) 40 k2 = 10^(2.84 - 2177.0 /TK ) 50 IF TC <= 25 THEN k3 = 10^(-5.86 - 317.0 / TK) 60 IF TC > 25 THEN k3 = 10^(-1.1 - 1737.0 / TK ) 80 IF M0 > 0 THEN area = PARM(1)*M0*(M/M0)^PARM(2) ELSE area = PARM(1)*M110 rate = area * (k1 * ACT("H+") + k2 * ACT("CO2") + k3 * ACT("H2O"))120 rate = rate * (1 - 10^(2/3*si_cc))130 moles = rate * 0.001 * TIME200 SAVE moles-endENDSOLUTION_SPECIESCO3-2 + 2 H+ = CO2 + H2O -log_k 16.681 -delta_h -5.738 kcal -analytic 464.1965 0.09344813 -26986.16 -165.75951 2248628.9 -dw 1.92e-9 -Vm 7.29 0.92 2.07 -1.23 -1.60 # ref. 1 + McBride et al. 2015, JCED 60, 1712CO2 = (CO2)2 # activity correction for CO2 solubility at high P, T -log_k -1.8 -analytical_expression 8.68 -0.0103 -2190 -Vm 14.58 1.84 4.14 -2.46 -3.20ENDPHASESCO2(g) CO2 = CO2 -log_k -1.468 -delta_h -4.776 kcal -analytic 10.5624 -2.3547e-2 -3972.8 0 5.8746e5 1.9194e-5 -T_c 304.2 # critical T, K -P_c 72.86 # critical P, atm -Omega 0.225 # acentric factorENDSOLUTION 1temp 25pressure 1pure waterUSE SOLUTION 1REACTION 1 Add minerals to waterHalite 0.85639Bischofite 0.75033Portlandite 0.29999Nahcolite 0.01939Thernardite 0.00364CaCl2:2H2O(cr) 0.30003SAVE solution 2ENDUSE SOLUTION 2REACTION_TEMPERATURE110#REACTION_PRESSURE#500SAVE solution 3ENDUSE SOLUTION 3GAS_PHASE 1 -fixed_pressure -pressure 500 -volume 1.53 -temperature 110 CO2(g) 500SAVE gas_phase 2SAVE solution 4ENDKINETICS 1Calcite -formula Calcite 1 -m 0.0625 -m0 0.0625 -parms 380000 0.6 -tol 1e-08-steps 200 in 10 steps # seconds-step_divide 1-runge_kutta 3-bad_step_max 500#INCREMENTAL_REACTIONSUSE SOLUTION 4USE GAS_PHASE 2REACTION_PRESSURE300END
You are on your own to develop your simulation.It appears you are using llnl.dat, although you have misspelled thenardite and CaCl2:2H2O(c) is not included. pitzer.dat is probably the best database for modeling the high concentrations associated with these minerals. If you do use pitzer.dat, you cannot easily define new SOLUTION_SPECIES because of all the parameters that are needed to ensure consistency.Note also that only phreeqc.dat, Amm.dat, and pitzer.dat have the molar volumes needed to model the effects of pressure. Look carefully at the output. Calcite is indeed supersaturated, but the pH of the final solution is 10.4.
ThernarditeNa2SO4 = 2.000Na+ + 1.000SO4-2 log_k -0.360 delta_h -2.200 #kJ/mol # Enthalpy of formation: -1387.82 #kJ/mol #98CHA -analytic -7.45423E-1 0E+0 1.14914E+2 0E+0 0E+0
In my searches on Google earlier today I came across this document.https://www.vtt.fi/inf/pdf/technology/2018/T321.pdf VTT TECHNOLOGY 321FINLAND Industrial and mine water chemistryAdvanced aqueous database for modelling industrial processesRisto Pajarre is the first authorAppendix D is a kinetically constrained CaCO3 Precipitation model. I have not looked at it in any detail, but I thought it may be helpful.