Download presentation
Presentation is loading. Please wait.
1
Introduction to PHREEQC—Chemistry for PHAST
2
PHAST Flow Transport HST3D—Flow and transport PHREEQC—Chemistry
Operator splitting—Sequential Non-Iterative Approach Chemistry Transport Flow
3
PHREEQC PHAST chemistry is inherited from PHREEQC
PHREEQC is run at the beginning of PHAST Solutions and reactants for initial conditions Solutions for boundary conditions PHREEQC is run cell-by-cell for each time step in the reactive-transport simulation
4
PHREEQC Reactants Keyword data blocks define reactants
SOLUTION—Solutions EQUILIBRIUM_PHASES—Equilibrium minerals and gases EXCHANGE—Exchangers SURFACE—Surfaces KINETICS and RATES—Kinetic reactions SOLID_SOLUTIONS—Solid solutions GAS_PHASE—gas bubble (rarely used) Store reactants on shelves by type and number
5
SOLUTION—Chemical Composition of a Water
Chemical analysis pH Temperature Major elements Ca, Mg, Na, K, Alkalinity, Cl, SO4 Trace elements Nutrients
6
SOLUTION Data Block SOLUTION 1: Oklahoma Brine units mol/kgw pH 5.713
temp Ca Mg Na Cl C S As (ug/kgw)
7
EQUILIBRIUM_PHASES Minerals and gases that react to equilibrium
Calcite reaction CaCO3 = Ca+2 + CO3-2 Equilibrium K = [Ca+2][CO3-2]
8
EQUILIBRIUM_PHASES Data Block
Mineral or gas Saturation state Amount Example EQUILIBRIUM_PHASES 5: CO2 Log PCO2 = -2, 10 moles Calcite equilibrium 1 moles Dolomite equilibrium 1 moles Fe(OH)3 equilibrium 0 moles
9
EXCHANGE Cation exchange composition
Reaction: Ca+2 + 2NaX = CaX2 + 2Na+ Equilibrium:
10
EXCHANGE Data Block Exchanger name Number of exchange sites
Chemical composition of exchanger Example EXCHANGE 15: CaX moles (X is defined in databases) NaX 0.05 moles Often X moles, Equilibrium with solution 1
11
SURFACE—Surface Composition Trace elements Zn, Cd, Pb, As, P
Reaction: Hfo_wOH + AsO4-3 = Hfo_wOHAsO4-3 Equilibrium:
12
SURFACE Data Block Example SURFACE 21:
Surface name—Hfo is Hydrous Ferric Oxide Number of surface sites Chemical composition of surface Example SURFACE 21: Hfo_wOH moles Hfo_sOH moles Often Hfo_w moles, Equilibrium with solution 1
13
KINETICS—Nonequilibrium Reactions
Monod Kinetics Radioactive decay Silicate hydrolosis Biological processes
14
KINETICS and RATES Data Blocks
Kinetic reaction name Stoichiometry of reaction Rate expression (RATES) Example KINETICS 21: DOC_decay formula Doc -1 CH2O +1 RATES 10 Rate = 0.01*TOT(“Doc”) 20 SAVE rate*TIME
15
PHREEQC—Reactions From the shelf To the beaker Kinetic reaction
Solution 1 Equilibrium phases 5 Surface 21 Kinetic reaction and equilibration
16
Arsenic in the Central Oklahoma Aquifer
Arsenic mostly in confined part of aquifer Arsenic associated with high pH Flow: unconfined to confined back to unconfined
17
Geochemical Reactions
Brine initially fills the aquifer Calcite and Dolomite equilibrium Cation exchange 2NaX + Ca+2 = CaX2 + 2Na+ 2NaX + Mg+2 = MgX2 + 2Na+ Surface complexation Hfo-HAsO4- + OH- = HfoOH + HAsO4-2 Desorption at pH > 8.5
18
Where we are headed Make a brine Define exchanger Define surface
Define recharge water Define minerals in aquifer Simulate inflow of recharge water into brine-filled aquifer
19
Solution Definition and Speciation Calculations
Mg Fe Cl HCO3 Inverse calculations Saturation Indices Speciation calculation Reaction calculations
20
PHREEQC Data Blocks SOLUTION—Define solution composition
SOLUTION_SPREAD—Spreadsheet input for solution composition Other data blocks related to speciation SOLUTION_MASTER_SPECIES—Redox states and gram formula weight SOLUTION_SPECIES—Reaction and log K
21
Seawater: units are ppm
Constituent Value pH pE Temperature Ca Mg Na K Fe Alkalinity as HCO3 Cl SO4 8.22 8.45 25 412.3 1291.8 10768 399.1 .002 19353 2712
22
PHREEQC Names and Default Gram Formula Weights
Species Default “as” phreeqc.dat/wateq4f.dat Alkalinity CaCO3 C Total carbon HCO3 C(4) TDIC C(-4) Methane CH4 N(5) Nitrate, NO3- N N(-3) Ammonium, NH4+ Si Silica SiO2 PO4 Phosphate P S(6) Sulfate SO4
23
Solution Data Block
24
pH, pe, Temperature
25
Solution Composition Set default units! Select analytes
Enter concen-trations Set “As”, special units Click OK when done
26
Run Speciation Calculation
Select files, phreeqc.dat
27
Exercise: Speciate seawater
Use PhreecI to run a speciation calculation for seawater using phreeqc.dat database. DATABASE C:\Program Files\USGS\Phreeqc Interactive \phreeqc.dat # seawater.pqi SOLUTION 1 Seawater temp pH pe redox pe units ppm density 1 Ca Mg Na K Fe Alkalinity as HCO3 Cl S(6) -water 1 # kg END
28
What is a speciation calculation?
Input: pH pe Concentrations Equations: Mass-balance—sum of the calcium species = total calcium Mass-action—activity of products divided by reactants = constant Activity coefficients—function of ionic strength Output Molalities, activities Saturation indices
29
pH = 6.3 + log[(HCO3-)/(CO2)]
What is pH? pH = log[(HCO3-)/(CO2)] Questions 1. How does the pH change when CO2 degasses during an alkalinity titration? 2. How does pH change when plankton respire CO2? 3. How does pH change when calcite dissolves? Questions 1. CO2 decreases, pH increases. 2. CO2 increases, pH decreases. 3. CaCO3 + CO2 + H2O = Ca+2 + 2HCO3-; CO2 decreases, HCO3- increases, pH increases.
![pH = log[(HCO3-)/(CO2)]](http://slideplayer.com/slide/7902981/25/images/29/pH+%3D+log%5B%28HCO3-%29%2F%28CO2%29%5D.jpg "What is pH pH = log[(HCO3-)/(CO2)] Questions. 1. How does the pH change when CO2 degasses during an alkalinity titration 2. How does pH change when plankton respire CO2 3. How does pH change when calcite dissolves Questions. 1. CO2 decreases, pH increases. 2. CO2 increases, pH decreases. 3. CaCO3 + CO2 + H2O = Ca+2 + 2HCO3-; CO2 decreases, HCO3- increases, pH increases.")
30
What is pe? Fe+2 = Fe+3 + e- pe = log( [Fe+3]/[Fe+2] ) + 13
HS- + 4H2O = SO H+ + 8e- pe = log( [SO4-2]/[HS-] ) – 9/8pH N2 + 6H2O = 2:NO H+ + 10e- pe = 0.1log( [NO3-]2/[N2] ) –1.2pH pe = 16.9Eh, Eh platinum electrode measurement
![What is pe Fe+2 = Fe+3 + e- pe = log( [Fe+3]/[Fe+2] ) + 13](http://slideplayer.com/slide/7902981/25/images/30/What+is+pe+Fe%2B2+%3D+Fe%2B3+%2B+e-+pe+%3D+log%28+%5BFe%2B3%5D%2F%5BFe%2B2%5D+%29+%2B+13.jpg "HS- + 4H2O = SO H+ + 8e- pe = log( [SO4-2]/[HS-] ) – 9/8pH N2 + 6H2O = 2:NO H+ + 10e- pe = 0.1log( [NO3-]2/[N2] ) –1.2pH pe = 16.9Eh, Eh platinum electrode measurement.")
31
Mass-Action Equations
H+ + CO3-2 = HCO3-
32
Mass Balance Calcium mass balance:
Catot = (Ca+2) + (CaSO4) + (CaHCO3+) + (CaCO3) + (CaOH+) + (CaHSO4+) In millimoles per kilogram of water: 10.7 = e-8
33
Activity Coefficients
WATEQ activity coefficient Davies activity coefficient Pitzer activity coefficients High ionic strength Limited model
34
Results of Speciation Calculation
Input file: H:\ntc\dk\phreeqc\seawater.pqi Output file: H:\ntc\dk\phreeqc\seawater.pqo Database file: C:\Program Files\USGS\Phreeqc Interactive \phreeqc.dat Reading data base. SOLUTION_MASTER_SPECIES SOLUTION_SPECIES PHASES EXCHANGE_MASTER_SPECIES EXCHANGE_SPECIES SURFACE_MASTER_SPECIES SURFACE_SPECIES RATES END Reading input data for simulation 1. DATABASE C:\Program Files\USGS\Phreeqc Interactive \phreeqc.dat SOLUTION 1 Seawater temp pH pe redox pe units ppm density 1 Ca Mg Na K Fe Alkalinity as HCO3 Cl S(6) water 1 # kg Beginning of initial solution calculations. Initial solution 1. Seawater Solution composition Elements Molality Moles Alkalinity e e-003 Ca e e-002 Cl e e-001 Fe e e-008 K e e-002 Mg e e-002 Na e e-001 S(6) e e-002 Description of solution pH = pe = Activity of water = Ionic strength = e-001 Mass of water (kg) = e+000 Total carbon (mol/kg) = e-003 Total CO2 (mol/kg) = e-003 Temperature (deg C) = Electrical balance (eq) = e-004 Percent error, 100*(Cat-|An|)/(Cat+|An|) = Iterations = 7 Total H = e+002 Total O = e+001 Distribution of species Log Log Log Species Molality Activity Molality Activity Gamma OH e e H e e H2O e e C(4) e-003 HCO e e MgHCO e e NaHCO e e MgCO e e NaCO e e CaHCO e e CO e e CaCO e e CO e e FeCO e e FeHCO e e Ca e-002 Ca e e CaSO e e CaOH e e CaHSO e e Cl e-001 Cl e e FeCl e e FeCl e e FeCl e e FeCl e e Fe(2) e-015 Fe e e FeSO e e FeOH e e FeHSO e e Fe(3) e-008 Fe(OH) e e Fe(OH) e e Fe(OH) e e FeOH e e FeSO e e Fe e e Fe(SO4) e e Fe2(OH) e e FeHSO e e Fe3(OH) e e H(0) e-037 H e e K e-002 K e e KSO e e KOH e e Mg e-002 Mg e e MgSO e e MgOH e e Na e-001 Na e e NaSO e e NaOH e e O(0) e-020 O e e S(6) e-002 SO e e HSO e e Saturation indices Phase SI log IAP log KT Anhydrite CaSO4 Aragonite CaCO3 Calcite CaCO3 CO2(g) CO2 Dolomite CaMg(CO3)2 Fe(OH)3(a) Fe(OH)3 Goethite FeOOH Gypsum CaSO4:2H2O H2(g) H2 H2O(g) H2O Halite NaCl Hematite Fe2O3 Jarosite-K KFe3(SO4)2(OH)6 Melanterite FeSO4:7H2O O2(g) O2 Siderite FeCO3 End of simulation. Reading input data for simulation 2. End of run.
35
SATURATION INDEX The thermodynamic state of a mineral relative to a solution
SI < 0, Mineral should dissolve SI > 0, Mineral should precipitate SI ~ 0, Mineral reacts fast enough to maintain equilibrium Maybe Kinetics Uncertainties
36
Useful Mineral List Minerals that may react to equilibrium relatively quickly
37
Other SOLUTION Capabilities
Define pe by ratio of redox states—O(0)/H2O, N(5)/N(-3), Fe(3)/Fe(2), S(6)/S(-2) Charge balance—pH or ionic element Adjust element concentration to phase boundary—Al to gibbsite Calculate pH from Alkalinity and C(4) (TDIC) SOLUTION_SPREAD—Spreadsheet format
38
Modifying the Database
Problems with arsenic thermo data Arsenic aqueous model (Nordstrom) not consistent with sorption model (Dzombak and Morel) Competition for surface sites between minor anion and major cations appears unrealistic
39
Arsenic Thermodynamic Data from Dzombak and Morel
SOLUTION_MASTER_SPECIES As H3AsO SOLUTION_SPECIES #H3AsO4 primary master species H3AsO4 = H3AsO4 log_k #H2AsO4- H3AsO4 = H2AsO4- + H+ log_k delta_h kcal #HAsO4-2 H3AsO4 = HAsO H+ log_k delta_h kcal #AsO4-3 H3AsO4 = AsO H+ log_k delta_h 3.43 kcal SOLUTION_MASTER_SPECIES As H3AsO SOLUTION_SPECIES #H3AsO4 primary master species H3AsO4 = H3AsO4 log_k #H2AsO4- H3AsO4 = H2AsO4- + H+ log_k delta_h kcal #HAsO4-2 H3AsO4 = HAsO H+ log_k delta_h kcal #AsO4-3 H3AsO4 = AsO H+ log_k delta_h 3.43 kcal
40
Arsenic Surface Complexation from Dzombak and Morel
SURFACE_MASTER_SPECIES Surf SurfOH SURFACE_SPECIES SurfOH = SurfOH log_k 0.0 SurfOH + H+ = SurfOH2+ log_k SurfOH = SurfO- + H+ log_k SurfOH + AsO H+ = SurfH2AsO4 + H2O log_k SurfOH + AsO H+ = SurfHAsO4- + H2O log_k SurfOH + AsO4-3 = SurfOHAsO4-3 log_k SURFACE_MASTER_SPECIES Surf SurfOH SURFACE_SPECIES SurfOH = SurfOH log_k 0.0 SurfOH + H+ = SurfOH2+ log_k SurfOH = SurfO- + H+ log_k SurfOH + AsO H+ = SurfH2AsO4 + H2O log_k SurfOH + AsO H+ = SurfHAsO4- + H2O log_k SurfOH + AsO4-3 = SurfOHAsO4-3 log_k
41
Exercise: Define Arsenic Chemistry
Cut and paste As aqueous species defined above Cut and paste As surface complexation defined above Add As to the SOLUTION definition for seawater 0.03 ppb Run speciation # sw_as.pqi SOLUTION_MASTER_SPECIES As H3AsO SOLUTION_SPECIES #H3AsO4 primary master species H3AsO4 = H3AsO4 log_k #H2AsO4- H3AsO4 = H2AsO4- + H+ log_k delta_h kcal #HAsO4-2 H3AsO4 = HAsO H+ log_k delta_h kcal #AsO4-3 H3AsO4 = AsO H+ log_k delta_h 3.43 kcal SURFACE_MASTER_SPECIES Surf SurfOH SURFACE_SPECIES SurfOH = SurfOH log_k 0.0 SurfOH + H+ = SurfOH2+ log_k SurfOH = SurfO- + H+ log_k SurfOH + AsO H+ = SurfH2AsO4 + H2O log_k SurfOH + AsO H+ = SurfHAsO4- + H2O log_k SurfOH + AsO4-3 = SurfOHAsO4-3 log_k SOLUTION 1 Seawater temp pH pe redox pe units ppm density 1 Ca Mg Na K Fe Alkalinity as HCO3 Cl S(6) As ppb -water 1 # kg END
42
Arsenic Speciation Arsenic has been added as a new element
Predominant species is HAsO4-2 at pH 8.22 Although not used yet, arsenic sorption has been defined Input file: H:\ntc\dk\phreeqc\sw_as.pqi Output file: H:\ntc\dk\phreeqc\sw_as.pqo Database file: C:\Program Files\USGS\Phreeqc Interactive \phreeqc.dat Reading data base. SOLUTION_MASTER_SPECIES SOLUTION_SPECIES PHASES EXCHANGE_MASTER_SPECIES EXCHANGE_SPECIES SURFACE_MASTER_SPECIES SURFACE_SPECIES RATES END Reading input data for simulation 1. DATABASE C:\Program Files\USGS\Phreeqc Interactive \phreeqc.dat As H3AsO H3AsO4 = H3AsO4 log_k H3AsO4 = H2AsO4- + H+ log_k delta_h kcal H3AsO4 = HAsO H+ log_k delta_h kcal H3AsO4 = AsO H+ log_k delta_h 3.43 kcal Surf SurfOH SurfOH = SurfOH log_k 0.0 SurfOH + H+ = SurfOH2+ log_k SurfOH = SurfO- + H+ log_k SurfOH + AsO H+ = SurfH2AsO4 + H2O log_k SurfOH + AsO H+ = SurfHAsO4- + H2O log_k SurfOH + AsO4-3 = SurfOHAsO4-3 log_k SOLUTION 1 Seawater temp pH pe redox pe units ppm density 1 Ca Mg Na K Fe Alkalinity as HCO3 Cl S(6) As ppb water 1 # kg Beginning of initial solution calculations. Initial solution 1. Seawater Solution composition Elements Molality Moles Alkalinity e e-003 As e e-010 Ca e e-002 Cl e e-001 Fe e e-008 K e e-002 Mg e e-002 Na e e-001 S(6) e e-002 Description of solution pH = pe = Activity of water = Ionic strength = e-001 Mass of water (kg) = e+000 Total carbon (mol/kg) = e-003 Total CO2 (mol/kg) = e-003 Temperature (deg C) = Electrical balance (eq) = e-004 Percent error, 100*(Cat-|An|)/(Cat+|An|) = Iterations = 7 Total H = e+002 Total O = e+001 Distribution of species Log Log Log Species Molality Activity Molality Activity Gamma OH e e H e e H2O e e As e-010 HAsO e e H2AsO e e AsO e e H3AsO e e C(4) e-003 HCO e e MgHCO e e NaHCO e e MgCO e e NaCO e e CaHCO e e CO e e CaCO e e CO e e FeCO e e FeHCO e e Ca e-002 Ca e e CaSO e e CaOH e e CaHSO e e Cl e-001 Cl e e FeCl e e FeCl e e FeCl e e FeCl e e Fe(2) e-015 Fe e e FeSO e e FeOH e e FeHSO e e Fe(3) e-008 Fe(OH) e e Fe(OH) e e Fe(OH) e e FeOH e e FeSO e e Fe e e Fe(SO4) e e Fe2(OH) e e FeHSO e e Fe3(OH) e e H(0) e-037 H e e K e-002 K e e KSO e e KOH e e Mg e-002 Mg e e MgSO e e MgOH e e Na e-001 Na e e NaSO e e NaOH e e O(0) e-020 O e e S(6) e-002 SO e e HSO e e Saturation indices Phase SI log IAP log KT Anhydrite CaSO4 Aragonite CaCO3 Calcite CaCO3 CO2(g) CO2 Dolomite CaMg(CO3)2 Fe(OH)3(a) Fe(OH)3 Goethite FeOOH Gypsum CaSO4:2H2O H2(g) H2 H2O(g) H2O Halite NaCl Hematite Fe2O3 Jarosite-K KFe3(SO4)2(OH)6 Melanterite FeSO4:7H2O O2(g) O2 Siderite FeCO3 End of simulation. Reading input data for simulation 2. End of run.
43
Reaction Calculations
SOLUTION MIX REACTION EQUILIBRIUM_PHASES EXCHANGE SURFACE KINETICS + EQUILIBRATION REACTOR SOLUTION EQUILIBRIUM_ PHASES EXCHANGE SURFACE KINETICS
44
EQUILIBRIUM REACTIONS
Can be used as PHAST initial conditions SURFACE EXCHANGE SOLID_SOLUTIONS EQUILIBRIUM_PHASES
45
NON-EQUILIBRIUM REACTIONS
REACTION_TEMPERATURE KINETICS (PHAST initial condition)
46
SAVE and USE Save results of calculations
Use previously defined SOLUTIONS, EQUILIBRIUM_PHASES, REACTIONs, etc Use previously SAVEd SOLUTIONS, EQUILBRIUM_PHASES, etc
47
Reactions Evaporating Seawater
48
PHREEQC Processing and Output
Initial-solution calculation Reaction calculation includes any of the following: Simulation/END EQUILIBRIUM_PHASES 2 SOLUTION 1 END MIX REACTION REACTION_TEMP EQUILIBRIUM_PHASES EXCHANGE SURFACE SOLID_SOLUTION GAS_PHASE KINETICS
49
Exercise: Evaporate Seawater
Append to input file and “save as” END USE solution 1 EQUILIBRIUM_PHASES 1 Halite SI = 0 Alternate formula is H2O Calcite—SI=0, moles=0 Dolomite—SI=0, moles=0 CO2(g)—SI=-1.5, moles=10 Anhydrite—SI=0, moles=0 Gypsum—SI=0, moles=0 SAVE solution 1 # sw_evap.pqi SOLUTION_MASTER_SPECIES As H3AsO SOLUTION_SPECIES #H3AsO4 primary master species H3AsO4 = H3AsO4 log_k #H2AsO4- H3AsO4 = H2AsO4- + H+ log_k delta_h kcal #HAsO4-2 H3AsO4 = HAsO H+ log_k delta_h kcal #AsO4-3 H3AsO4 = AsO H+ log_k delta_h 3.43 kcal SURFACE_MASTER_SPECIES Surf SurfOH SURFACE_SPECIES SurfOH = SurfOH log_k 0.0 SurfOH + H+ = SurfOH2+ log_k SurfOH = SurfO- + H+ log_k SurfOH + AsO H+ = SurfH2AsO4 + H2O log_k SurfOH + AsO H+ = SurfHAsO4- + H2O log_k SurfOH + AsO4-3 = SurfOHAsO4-3 log_k SOLUTION 1 Seawater temp pH pe redox pe units ppm density 1 Ca Mg Na K Fe Alkalinity as HCO3 Cl S(6) As ppb -water 1 # kg END USE solution 1 EQUILIBRIUM_PHASES Halite 0 H2O Dolomite 0 0 Calcite 0 10 Gypsum 0 0 Anhydrite 0 0 CO2(g) -1.5 SAVE solution 1
50
Exercise: Evaporate Seawater
How much water remains? What is the concentration of Na, Cl? Input file: H:\ntc\dk\phreeqc\sw_evap.pqi Output file: H:\ntc\dk\phreeqc\sw_evap.pqo Database file: C:\Program Files\USGS\Phreeqc Interactive \phreeqc.dat Reading data base. SOLUTION_MASTER_SPECIES SOLUTION_SPECIES PHASES EXCHANGE_MASTER_SPECIES EXCHANGE_SPECIES SURFACE_MASTER_SPECIES SURFACE_SPECIES RATES END Reading input data for simulation 1. DATABASE C:\Program Files\USGS\Phreeqc Interactive \phreeqc.dat As H3AsO H3AsO4 = H3AsO4 log_k H3AsO4 = H2AsO4- + H+ log_k delta_h kcal H3AsO4 = HAsO H+ log_k delta_h kcal H3AsO4 = AsO H+ log_k delta_h 3.43 kcal Surf SurfOH SurfOH = SurfOH log_k 0.0 SurfOH + H+ = SurfOH2+ log_k SurfOH = SurfO- + H+ log_k SurfOH + AsO H+ = SurfH2AsO4 + H2O log_k SurfOH + AsO H+ = SurfHAsO4- + H2O log_k SurfOH + AsO4-3 = SurfOHAsO4-3 log_k SOLUTION 1 Seawater temp pH pe redox pe units ppm density 1 Ca Mg Na K Fe Alkalinity as HCO3 Cl S(6) As ppb water 1 # kg Beginning of initial solution calculations. Initial solution 1. Seawater Solution composition Elements Molality Moles Alkalinity e e-003 As e e-010 Ca e e-002 Cl e e-001 Fe e e-008 K e e-002 Mg e e-002 Na e e-001 S(6) e e-002 Description of solution pH = pe = Activity of water = Ionic strength = e-001 Mass of water (kg) = e+000 Total carbon (mol/kg) = e-003 Total CO2 (mol/kg) = e-003 Temperature (deg C) = Electrical balance (eq) = e-004 Percent error, 100*(Cat-|An|)/(Cat+|An|) = Iterations = 7 Total H = e+002 Total O = e+001 Distribution of species Log Log Log Species Molality Activity Molality Activity Gamma OH e e H e e H2O e e As e-010 HAsO e e H2AsO e e AsO e e H3AsO e e C(4) e-003 HCO e e MgHCO e e NaHCO e e MgCO e e NaCO e e CaHCO e e CO e e CaCO e e CO e e FeCO e e FeHCO e e Ca e-002 Ca e e CaSO e e CaOH e e CaHSO e e Cl e-001 Cl e e FeCl e e FeCl e e FeCl e e FeCl e e Fe(2) e-015 Fe e e FeSO e e FeOH e e FeHSO e e Fe(3) e-008 Fe(OH) e e Fe(OH) e e Fe(OH) e e FeOH e e FeSO e e Fe e e Fe(SO4) e e Fe2(OH) e e FeHSO e e Fe3(OH) e e H(0) e-037 H e e K e-002 K e e KSO e e KOH e e Mg e-002 Mg e e MgSO e e MgOH e e Na e-001 Na e e NaSO e e NaOH e e O(0) e-020 O e e S(6) e-002 SO e e HSO e e Saturation indices Phase SI log IAP log KT Anhydrite CaSO4 Aragonite CaCO3 Calcite CaCO3 CO2(g) CO2 Dolomite CaMg(CO3)2 Fe(OH)3(a) Fe(OH)3 Goethite FeOOH Gypsum CaSO4:2H2O H2(g) H2 H2O(g) H2O Halite NaCl Hematite Fe2O3 Jarosite-K KFe3(SO4)2(OH)6 Melanterite FeSO4:7H2O O2(g) O2 Siderite FeCO3 End of simulation. Reading input data for simulation 2. USE solution 1 EQUILIBRIUM_PHASES Halite 0 H2O Dolomite 0 0 Calcite 0 10 Gypsum 0 0 Anhydrite 0 0 CO2(g) -1.5 SAVE solution 1 Beginning of batch-reaction calculations. Reaction step 1. Using solution 1. Seawater Using pure phase assemblage 1. Phase assemblage Moles in assemblage Phase SI log IAP log KT Initial Final Delta Anhydrite e e+000 Calcite e e e-002 CO2(g) e e e-004 Dolomite e e e-002 Gypsum e e e-002 Halite H2O is reactant e e e+001 As e e-010 C e e-004 Ca e e-002 Cl e e-001 Fe e e-008 K e e-002 Mg e e-003 Na e e-001 S e e-004 pH = Charge balance pe = Adjusted to redox equilibrium Activity of water = Ionic strength = e+000 Mass of water (kg) = e-002 Total alkalinity (eq/kg) = e-003 Total CO2 (mol/kg) = e-003 Iterations = 19 Total H = e+000 Total O = e+000 H e e OH e e H2O e e As e-009 H2AsO e e HAsO e e H3AsO e e AsO e e C(-4) e+000 CH e e C(4) e-003 CaHCO e e HCO e e NaHCO e e CO e e MgHCO e e CaCO e e MgCO e e NaCO e e CO e e FeHCO e e FeCO e e Ca e-001 Ca e e CaSO e e CaHSO e e CaOH e e Cl e+000 Cl e e FeCl e e FeCl e e FeCl e e FeCl e e Fe(2) e-011 Fe e e FeSO e e FeOH e e FeHSO e e Fe(HS) e e Fe(HS) e e Fe(3) e-007 Fe(OH) e e Fe(OH) e e Fe e e FeOH e e Fe(OH) e e FeSO e e Fe(SO4) e e FeHSO e e Fe2(OH) e e Fe3(OH) e e H(0) e+000 H e e K e-001 K e e KSO e e KOH e e Mg e-001 Mg e e MgSO e e MgOH e e Na e+000 Na e e NaSO e e NaOH e e O(0) e-011 O e e S(-2) e+000 H2S e e HS e e S e e S(6) e-003 SO e e HSO e e Anhydrite CaSO4 Aragonite CaCO3 Calcite CaCO3 CH4(g) CH4 CO2(g) CO2 Dolomite CaMg(CO3)2 Fe(OH)3(a) Fe(OH)3 FeS(ppt) FeS Goethite FeOOH Gypsum CaSO4:2H2O H2(g) H2 H2O(g) H2O H2S(g) H2S Halite NaCl Hematite Fe2O3 Jarosite-K KFe3(SO4)2(OH)6 Mackinawite FeS Melanterite FeSO4:7H2O O2(g) O2 Pyrite FeS2 Siderite FeCO3 Sulfur S Reading input data for simulation 3. End of run.
51
Exercise: Surface composition in equilibrium with brine
Define a SURFACE 1 Equilibrium with solution 1 SurfOH 0.14 moles of sites 600 m2/g 30 g # sw_ex_surf.pqi SOLUTION_MASTER_SPECIES As H3AsO SOLUTION_SPECIES #H3AsO4 primary master species H3AsO4 = H3AsO4 log_k #H2AsO4- H3AsO4 = H2AsO4- + H+ log_k delta_h kcal #HAsO4-2 H3AsO4 = HAsO H+ log_k delta_h kcal #AsO4-3 H3AsO4 = AsO H+ log_k delta_h 3.43 kcal SURFACE_MASTER_SPECIES Surf SurfOH SURFACE_SPECIES SurfOH = SurfOH log_k 0.0 SurfOH + H+ = SurfOH2+ log_k SurfOH = SurfO- + H+ log_k SurfOH + AsO H+ = SurfH2AsO4 + H2O log_k SurfOH + AsO H+ = SurfHAsO4- + H2O log_k SurfOH + AsO4-3 = SurfOHAsO4-3 log_k SOLUTION 1 Seawater temp pH pe redox pe units ppm density 1 Ca Mg Na K Fe Alkalinity as HCO3 Cl S(6) As ppb -water 1 # kg END USE solution 1 EQUILIBRIUM_PHASES Halite 0 H2O Dolomite 0 0 Calcite 0 10 Gypsum 0 0 Anhydrite 0 0 CO2(g) -1.5 SAVE solution 1 SURFACE 1 Surface in equilibrium with brine -equilibrate with solution 1 Surf EXCHANGE 1 X
52
Exercise: Exchange composition in equilibrium with brine
Define EXCHANGE 1 Equilibrium with solution 1 0.4 moles of exchange sites Input file: H:\ntc\dk\phreeqc\sw_ex_surf.pqi Output file: H:\ntc\dk\phreeqc\sw_ex_surf.pqo Database file: C:\Program Files\USGS\Phreeqc Interactive \phreeqc.dat Reading data base. SOLUTION_MASTER_SPECIES SOLUTION_SPECIES PHASES EXCHANGE_MASTER_SPECIES EXCHANGE_SPECIES SURFACE_MASTER_SPECIES SURFACE_SPECIES RATES END Reading input data for simulation 1. DATABASE C:\Program Files\USGS\Phreeqc Interactive \phreeqc.dat As H3AsO H3AsO4 = H3AsO4 log_k H3AsO4 = H2AsO4- + H+ log_k delta_h kcal H3AsO4 = HAsO H+ log_k delta_h kcal H3AsO4 = AsO H+ log_k delta_h 3.43 kcal Surf SurfOH SurfOH = SurfOH log_k 0.0 SurfOH + H+ = SurfOH2+ log_k SurfOH = SurfO- + H+ log_k SurfOH + AsO H+ = SurfH2AsO4 + H2O log_k SurfOH + AsO H+ = SurfHAsO4- + H2O log_k SurfOH + AsO4-3 = SurfOHAsO4-3 log_k SOLUTION 1 Seawater temp pH pe redox pe units ppm density 1 Ca Mg Na K Fe Alkalinity as HCO3 Cl S(6) As ppb water 1 # kg Beginning of initial solution calculations. Initial solution 1. Seawater Solution composition Elements Molality Moles Alkalinity e e-003 As e e-010 Ca e e-002 Cl e e-001 Fe e e-008 K e e-002 Mg e e-002 Na e e-001 S(6) e e-002 Description of solution pH = pe = Activity of water = Ionic strength = e-001 Mass of water (kg) = e+000 Total carbon (mol/kg) = e-003 Total CO2 (mol/kg) = e-003 Temperature (deg C) = Electrical balance (eq) = e-004 Percent error, 100*(Cat-|An|)/(Cat+|An|) = Iterations = 7 Total H = e+002 Total O = e+001 Distribution of species Log Log Log Species Molality Activity Molality Activity Gamma OH e e H e e H2O e e As e-010 HAsO e e H2AsO e e AsO e e H3AsO e e C(4) e-003 HCO e e MgHCO e e NaHCO e e MgCO e e NaCO e e CaHCO e e CO e e CaCO e e CO e e FeCO e e FeHCO e e Ca e-002 Ca e e CaSO e e CaOH e e CaHSO e e Cl e-001 Cl e e FeCl e e FeCl e e FeCl e e FeCl e e Fe(2) e-015 Fe e e FeSO e e FeOH e e FeHSO e e Fe(3) e-008 Fe(OH) e e Fe(OH) e e Fe(OH) e e FeOH e e FeSO e e Fe e e Fe(SO4) e e Fe2(OH) e e FeHSO e e Fe3(OH) e e H(0) e-037 H e e K e-002 K e e KSO e e KOH e e Mg e-002 Mg e e MgSO e e MgOH e e Na e-001 Na e e NaSO e e NaOH e e O(0) e-020 O e e S(6) e-002 SO e e HSO e e Saturation indices Phase SI log IAP log KT Anhydrite CaSO4 Aragonite CaCO3 Calcite CaCO3 CO2(g) CO2 Dolomite CaMg(CO3)2 Fe(OH)3(a) Fe(OH)3 Goethite FeOOH Gypsum CaSO4:2H2O H2(g) H2 H2O(g) H2O Halite NaCl Hematite Fe2O3 Jarosite-K KFe3(SO4)2(OH)6 Melanterite FeSO4:7H2O O2(g) O2 Siderite FeCO3 End of simulation. Reading input data for simulation 2. USE solution 1 EQUILIBRIUM_PHASES Halite 0 H2O Dolomite 0 0 Calcite 0 10 Gypsum 0 0 Anhydrite 0 0 CO2(g) -1.5 SAVE solution 1 Beginning of batch-reaction calculations. Reaction step 1. Using solution 1. Seawater Using pure phase assemblage 1. Phase assemblage Moles in assemblage Phase SI log IAP log KT Initial Final Delta Anhydrite e e+000 Calcite e e e-002 CO2(g) e e e-004 Dolomite e e e-002 Gypsum e e e-002 Halite H2O is reactant e e e+001 As e e-010 C e e-004 Ca e e-002 Cl e e-001 Fe e e-008 K e e-002 Mg e e-003 Na e e-001 S e e-004 pH = Charge balance pe = Adjusted to redox equilibrium Activity of water = Ionic strength = e+000 Mass of water (kg) = e-002 Total alkalinity (eq/kg) = e-003 Total CO2 (mol/kg) = e-003 Iterations = 19 Total H = e+000 Total O = e+000 H e e OH e e H2O e e As e-009 H2AsO e e HAsO e e H3AsO e e AsO e e C(-4) e+000 CH e e C(4) e-003 CaHCO e e HCO e e NaHCO e e CO e e MgHCO e e CaCO e e MgCO e e NaCO e e CO e e FeHCO e e FeCO e e Ca e-001 Ca e e CaSO e e CaHSO e e CaOH e e Cl e+000 Cl e e FeCl e e FeCl e e FeCl e e FeCl e e Fe(2) e-011 Fe e e FeSO e e FeOH e e FeHSO e e Fe(HS) e e Fe(HS) e e Fe(3) e-007 Fe(OH) e e Fe(OH) e e Fe e e FeOH e e Fe(OH) e e FeSO e e Fe(SO4) e e FeHSO e e Fe2(OH) e e Fe3(OH) e e H(0) e+000 H e e K e-001 K e e KSO e e KOH e e Mg e-001 Mg e e MgSO e e MgOH e e Na e+000 Na e e NaSO e e NaOH e e O(0) e-011 O e e S(-2) e+000 H2S e e HS e e S e e S(6) e-003 SO e e HSO e e Anhydrite CaSO4 Aragonite CaCO3 Calcite CaCO3 CH4(g) CH4 CO2(g) CO2 Dolomite CaMg(CO3)2 Fe(OH)3(a) Fe(OH)3 FeS(ppt) FeS Goethite FeOOH Gypsum CaSO4:2H2O H2(g) H2 H2O(g) H2O H2S(g) H2S Halite NaCl Hematite Fe2O3 Jarosite-K KFe3(SO4)2(OH)6 Mackinawite FeS Melanterite FeSO4:7H2O O2(g) O2 Pyrite FeS2 Siderite FeCO3 Sulfur S Reading input data for simulation 3. SURFACE 1 Surface in equilibrium with brine equilibrate with solution 1 Surf Beginning of initial surface-composition calculations. Surface 1. Surface in equilibrium with brine Surf 8.181e-002 Surface charge, eq 4.386e-001 sigma, C/m**2 5.857e-002 psi, V -2.280e F*psi/RT 1.023e-001 exp(-F*psi/RT) 6.000e+002 specific area, m**2/g 1.800e+004 m**2 for e+001 g 1.400e-001 moles Mole Log Species Moles Fraction Molality Molality SurfOH e e SurfOH e e SurfOHAsO e e SurfHAsO e e SurfO e e SurfH2AsO e e Reading input data for simulation 4. EXCHANGE 1 X Beginning of initial exchange-composition calculations. Exchange 1. X e-001 mol Equiv- Equivalent Log Species Moles alents Fraction Gamma NaX e e e KX e e e CaX e e e MgX e e e FeX e e e Reading input data for simulation 5. End of run.
53
Exercise: Make a Carbonate Ground Water
Append to same file END Start with pure water (solution 2) Equilibrate with calcite and dolomite PCO2 = -1.5 Save result as solution 2 # gw.pqi SOLUTION_MASTER_SPECIES As H3AsO SOLUTION_SPECIES #H3AsO4 primary master species H3AsO4 = H3AsO4 log_k #H2AsO4- H3AsO4 = H2AsO4- + H+ log_k delta_h kcal #HAsO4-2 H3AsO4 = HAsO H+ log_k delta_h kcal #AsO4-3 H3AsO4 = AsO H+ log_k delta_h 3.43 kcal SURFACE_MASTER_SPECIES Surf SurfOH SURFACE_SPECIES SurfOH = SurfOH log_k 0.0 SurfOH + H+ = SurfOH2+ log_k SurfOH = SurfO- + H+ log_k SurfOH + AsO H+ = SurfH2AsO4 + H2O log_k SurfOH + AsO H+ = SurfHAsO4- + H2O log_k SurfOH + AsO4-3 = SurfOHAsO4-3 log_k SOLUTION 1 Seawater temp pH pe redox pe units ppm density 1 Ca Mg Na K Fe Alkalinity as HCO3 Cl S(6) As ppb -water 1 # kg END USE solution 1 EQUILIBRIUM_PHASES Halite 0 H2O Dolomite 0 0 Calcite 0 10 Gypsum 0 0 Anhydrite 0 0 CO2(g) -1.5 SAVE solution 1 SURFACE 1 Surface in equilibrium with brine -equilibrate with solution 1 Surf EXCHANGE 1 X SOLUTION 2 Pure water EQUILIBRIUM_PHASES 2 Calcite 0 10 Dolomite 0 10 CO2(g) SAVE solution 2
54
Comprehensive Exam We want to simulate the reactions of carbonate ground water with the aquifer sediments Assume the aquifer initially contains a surface and exchanger that have been equilibrated with the brine as well as calcite and dolomite Simulate a volume of aquifer that sequentially receives 4 volumes of carbonate ground water What pH and arsenic concentrations do you find in each volume of pore water? # reaction.pqi SOLUTION_MASTER_SPECIES As H3AsO SOLUTION_SPECIES #H3AsO4 primary master species H3AsO4 = H3AsO4 log_k #H2AsO4- H3AsO4 = H2AsO4- + H+ log_k delta_h kcal #HAsO4-2 H3AsO4 = HAsO H+ log_k delta_h kcal #AsO4-3 H3AsO4 = AsO H+ log_k delta_h 3.43 kcal SURFACE_MASTER_SPECIES Surf SurfOH SURFACE_SPECIES SurfOH = SurfOH log_k 0.0 SurfOH + H+ = SurfOH2+ log_k SurfOH = SurfO- + H+ log_k SurfOH + AsO H+ = SurfH2AsO4 + H2O log_k SurfOH + AsO H+ = SurfHAsO4- + H2O log_k SurfOH + AsO4-3 = SurfOHAsO4-3 log_k SOLUTION 1 Seawater temp pH pe redox pe units ppm density 1 Ca Mg Na K Fe Alkalinity as HCO3 Cl S(6) As ppb -water 1 # kg END USE solution 1 EQUILIBRIUM_PHASES Halite 0 H2O Dolomite 0 0 Calcite 0 10 Gypsum 0 0 Anhydrite 0 0 CO2(g) -1.5 SAVE solution 1 SURFACE 1 Surface in equilibrium with brine -equilibrate with solution 1 Surf EXCHANGE 1 X SOLUTION 2 Pure water EQUILIBRIUM_PHASES 2 Calcite 0 10 Dolomite 0 10 CO2(g) SAVE solution 2 EQUILIBRIUM_PHASES 1 Calcite Dolomite USER_PUNCH # Prints concentrations in mg/kgw to reaction.sel SELECTED_OUTPUT -file reaction.sel -reset false -ph true -headings Ca Mg Na Cl TDIC SO4 As -start 10 PUNCH TOT("Ca")*1000*40.08 20 PUNCH TOT("Mg")*1000*24.3 30 PUNCH TOT("Na")*1000*23 40 PUNCH TOT("Cl")*1000*35.5 50 PUNCH TOT("C(4)")*1000*61 60 PUNCH TOT("S(6)")*1000*96 70 PUNCH TOT("As")*1000*1000*74.3 -end USE solution 2 USE equilibrium_phases 1 USE surface 1 USE exchange 1 SAVE equilibrium_phases 1 SAVE surface 1 SAVE exchange 1
55
Chemical Reactions Ca, Mg exchanged for Na Calcite, dolomite dissolve
pH increases Arsenic is released from surface sites Input file: H:\ntc\dk\phreeqc\reaction.pqi Output file: H:\ntc\dk\phreeqc\reaction.pqo Database file: C:\Program Files\USGS\Phreeqc Interactive \phreeqc.dat Reading data base. SOLUTION_MASTER_SPECIES SOLUTION_SPECIES PHASES EXCHANGE_MASTER_SPECIES EXCHANGE_SPECIES SURFACE_MASTER_SPECIES SURFACE_SPECIES RATES END Reading input data for simulation 1. DATABASE C:\Program Files\USGS\Phreeqc Interactive \phreeqc.dat As H3AsO H3AsO4 = H3AsO4 log_k H3AsO4 = H2AsO4- + H+ log_k delta_h kcal H3AsO4 = HAsO H+ log_k delta_h kcal H3AsO4 = AsO H+ log_k delta_h 3.43 kcal Surf SurfOH SurfOH = SurfOH log_k 0.0 SurfOH + H+ = SurfOH2+ log_k SurfOH = SurfO- + H+ log_k SurfOH + AsO H+ = SurfH2AsO4 + H2O log_k SurfOH + AsO H+ = SurfHAsO4- + H2O log_k SurfOH + AsO4-3 = SurfOHAsO4-3 log_k SOLUTION 1 Seawater temp pH pe redox pe units ppm density 1 Ca Mg Na K Fe Alkalinity as HCO3 Cl S(6) As ppb water 1 # kg Beginning of initial solution calculations. Initial solution 1. Seawater Solution composition Elements Molality Moles Alkalinity e e-003 As e e-010 Ca e e-002 Cl e e-001 Fe e e-008 K e e-002 Mg e e-002 Na e e-001 S(6) e e-002 Description of solution pH = pe = Activity of water = Ionic strength = e-001 Mass of water (kg) = e+000 Total carbon (mol/kg) = e-003 Total CO2 (mol/kg) = e-003 Temperature (deg C) = Electrical balance (eq) = e-004 Percent error, 100*(Cat-|An|)/(Cat+|An|) = Iterations = 7 Total H = e+002 Total O = e+001 Distribution of species Log Log Log Species Molality Activity Molality Activity Gamma OH e e H e e H2O e e As e-010 HAsO e e H2AsO e e AsO e e H3AsO e e C(4) e-003 HCO e e MgHCO e e NaHCO e e MgCO e e NaCO e e CaHCO e e CO e e CaCO e e CO e e FeCO e e FeHCO e e Ca e-002 Ca e e CaSO e e CaOH e e CaHSO e e Cl e-001 Cl e e FeCl e e FeCl e e FeCl e e FeCl e e Fe(2) e-015 Fe e e FeSO e e FeOH e e FeHSO e e Fe(3) e-008 Fe(OH) e e Fe(OH) e e Fe(OH) e e FeOH e e FeSO e e Fe e e Fe(SO4) e e Fe2(OH) e e FeHSO e e Fe3(OH) e e H(0) e-037 H e e K e-002 K e e KSO e e KOH e e Mg e-002 Mg e e MgSO e e MgOH e e Na e-001 Na e e NaSO e e NaOH e e O(0) e-020 O e e S(6) e-002 SO e e HSO e e Saturation indices Phase SI log IAP log KT Anhydrite CaSO4 Aragonite CaCO3 Calcite CaCO3 CO2(g) CO2 Dolomite CaMg(CO3)2 Fe(OH)3(a) Fe(OH)3 Goethite FeOOH Gypsum CaSO4:2H2O H2(g) H2 H2O(g) H2O Halite NaCl Hematite Fe2O3 Jarosite-K KFe3(SO4)2(OH)6 Melanterite FeSO4:7H2O O2(g) O2 Siderite FeCO3 End of simulation. Reading input data for simulation 2. USE solution 1 EQUILIBRIUM_PHASES Halite 0 H2O Dolomite 0 0 Calcite 0 10 Gypsum 0 0 Anhydrite 0 0 CO2(g) -1.5 SAVE solution 1 Beginning of batch-reaction calculations. Reaction step 1. Using solution 1. Seawater Using pure phase assemblage 1. Phase assemblage Moles in assemblage Phase SI log IAP log KT Initial Final Delta Anhydrite e e+000 Calcite e e e-002 CO2(g) e e e-004 Dolomite e e e-002 Gypsum e e e-002 Halite H2O is reactant e e e+001 As e e-010 C e e-004 Ca e e-002 Cl e e-001 Fe e e-008 K e e-002 Mg e e-003 Na e e-001 S e e-004 pH = Charge balance pe = Adjusted to redox equilibrium Activity of water = Ionic strength = e+000 Mass of water (kg) = e-002 Total alkalinity (eq/kg) = e-003 Total CO2 (mol/kg) = e-003 Iterations = 19 Total H = e+000 Total O = e+000 H e e OH e e H2O e e As e-009 H2AsO e e HAsO e e H3AsO e e AsO e e C(-4) e+000 CH e e C(4) e-003 CaHCO e e HCO e e NaHCO e e CO e e MgHCO e e CaCO e e MgCO e e NaCO e e CO e e FeHCO e e FeCO e e Ca e-001 Ca e e CaSO e e CaHSO e e CaOH e e Cl e+000 Cl e e FeCl e e FeCl e e FeCl e e FeCl e e Fe(2) e-011 Fe e e FeSO e e FeOH e e FeHSO e e Fe(HS) e e Fe(HS) e e Fe(3) e-007 Fe(OH) e e Fe(OH) e e Fe e e FeOH e e Fe(OH) e e FeSO e e Fe(SO4) e e FeHSO e e Fe2(OH) e e Fe3(OH) e e H(0) e+000 H e e K e-001 K e e KSO e e KOH e e Mg e-001 Mg e e MgSO e e MgOH e e Na e+000 Na e e NaSO e e NaOH e e O(0) e-011 O e e S(-2) e+000 H2S e e HS e e S e e S(6) e-003 SO e e HSO e e Anhydrite CaSO4 Aragonite CaCO3 Calcite CaCO3 CH4(g) CH4 CO2(g) CO2 Dolomite CaMg(CO3)2 Fe(OH)3(a) Fe(OH)3 FeS(ppt) FeS Goethite FeOOH Gypsum CaSO4:2H2O H2(g) H2 H2O(g) H2O H2S(g) H2S Halite NaCl Hematite Fe2O3 Jarosite-K KFe3(SO4)2(OH)6 Mackinawite FeS Melanterite FeSO4:7H2O O2(g) O2 Pyrite FeS2 Siderite FeCO3 Sulfur S Reading input data for simulation 3. SURFACE 1 Surface in equilibrium with brine equilibrate with solution 1 Surf Beginning of initial surface-composition calculations. Surface 1. Surface in equilibrium with brine Surf 8.181e-002 Surface charge, eq 4.386e-001 sigma, C/m**2 5.857e-002 psi, V -2.280e F*psi/RT 1.023e-001 exp(-F*psi/RT) 6.000e+002 specific area, m**2/g 1.800e+004 m**2 for e+001 g 1.400e-001 moles Mole Log Species Moles Fraction Molality Molality SurfOH e e SurfOH e e SurfOHAsO e e SurfHAsO e e SurfO e e SurfH2AsO e e Reading input data for simulation 4. EXCHANGE 1 X Beginning of initial exchange-composition calculations. Exchange 1. X e-001 mol Equiv- Equivalent Log Species Moles alents Fraction Gamma NaX e e e KX e e e CaX e e e MgX e e e FeX e e e Reading input data for simulation 5. SOLUTION 2 Pure water EQUILIBRIUM_PHASES 2 Calcite 0 10 Dolomite 0 10 CO2(g) SAVE solution 2 Initial solution 2. Pure water Pure water pH = pe = Activity of water = Ionic strength = e-007 Total alkalinity (eq/kg) = e-010 Total carbon (mol/kg) = e+000 Total CO2 (mol/kg) = e+000 Electrical balance (eq) = e-010 Percent error, 100*(Cat-|An|)/(Cat+|An|) = Iterations = 0 Total H = e+002 Total O = e+001 OH e e H e e H2O e e H(0) e-025 H e e O(0) e+000 O e e H2(g) H2 H2O(g) H2O O2(g) O2 Using solution 2. Pure water Using pure phase assemblage 2. Calcite e e e-004 CO2(g) e e e-003 Dolomite e e e-003 C e e-003 Ca e e-003 Mg e e-003 pH = Charge balance pe = Adjusted to redox equilibrium Ionic strength = e-003 Mass of water (kg) = e-001 Total alkalinity (eq/kg) = e-003 Total CO2 (mol/kg) = e-003 Percent error, 100*(Cat-|An|)/(Cat+|An|) = Iterations = 17 Total O = e+001 OH e e H e e H2O e e C(-4) e-024 CH e e C(4) e-003 HCO e e CO e e CaHCO e e MgHCO e e CaCO e e CO e e MgCO e e Ca e-003 Ca e e CaOH e e H(0) e-015 H e e Mg e-003 Mg e e MgOH e e O e e CH4(g) CH4 Dolomite CaMg(CO3)2 H2(g) H2 H2O(g) H2O O2(g) O2 Reading input data for simulation 6. EQUILIBRIUM_PHASES 1 Calcite Dolomite Reading input data for simulation 7. USER_PUNCH SELECTED_OUTPUT file reaction.sel reset false ph true headings Ca Mg Na Cl TDIC SO4 As start 10 PUNCH TOT("Ca")*1000*40.08 20 PUNCH TOT("Mg")*1000*24.3 30 PUNCH TOT("Na")*1000*23 40 PUNCH TOT("Cl")*1000*35.5 50 PUNCH TOT("C(4)")*1000*61 60 PUNCH TOT("S(6)")*1000*96 70 PUNCH TOT("As")*1000*1000*74.3 end USE solution 2 USE equilibrium_phases 1 USE surface 1 USE exchange 1 SAVE equilibrium_phases 1 SAVE surface 1 SAVE exchange 1 Using solution 2. Solution after simulation 5. Using exchange 1. Exchange assemblage after simulation 4. Using surface 1. Surface assemblage after simulation 3. Calcite e e e-002 Dolomite e e e-002 Surface composition 9.764e-003 Surface charge, eq 5.234e-002 sigma, C/m**2 6.343e-002 psi, V -2.469e F*psi/RT 8.467e-002 exp(-F*psi/RT) SurfOH e e SurfOH e e SurfOHAsO e e SurfO e e SurfHAsO e e SurfH2AsO e e Exchange composition NaX e e e CaX e e e KX e e e MgX e e e FeX e e e As e e-010 C e e-002 Ca e e-003 Fe e e-014 K e e-003 Mg e e-003 Na e e-001 pH = Charge balance pe = Adjusted to redox equilibrium Activity of water = Ionic strength = e-002 Total alkalinity (eq/kg) = e-002 Total CO2 (mol/kg) = e-002 Electrical balance (eq) = e-002 Percent error, 100*(Cat-|An|)/(Cat+|An|) = Iterations = 14 Total H = e+002 Total O = e+001 H e e OH e e H2O e e As e-010 HAsO e e H2AsO e e AsO e e H3AsO e e C(-4) e-021 CH e e C(4) e-002 HCO e e CO e e NaHCO e e CaHCO e e MgHCO e e CO e e NaCO e e CaCO e e MgCO e e FeHCO e e FeCO e e Ca e-003 Ca e e CaOH e e Fe(2) e-014 Fe e e FeOH e e Fe(3) e-021 Fe(OH) e e Fe(OH) e e Fe(OH) e e FeOH e e Fe e e Fe2(OH) e e Fe3(OH) e e H(0) e-014 H e e K e-003 K e e KOH e e Mg e-003 Mg e e MgOH e e Na e-001 Na e e NaOH e e O e e CH4(g) CH4 CO2(g) CO2 Fe(OH)3(a) Fe(OH)3 Goethite FeOOH H2(g) H2 Hematite Fe2O3 O2(g) O2 Siderite FeCO3 Reading input data for simulation 8. Using exchange 1. Exchange assemblage after simulation 7. Using surface 1. Surface assemblage after simulation 7. Using pure phase assemblage 1. Pure-phase assemblage after simulation 7. Calcite e e e-003 Dolomite e e e-003 -2.130e-004 Surface charge, eq -1.142e-003 sigma, C/m**2 -3.320e-003 psi, V 1.292e F*psi/RT 1.138e+000 exp(-F*psi/RT) SurfOH e e SurfOH e e SurfO e e SurfOHAsO e e SurfHAsO e e SurfH2AsO e e NaX e e e CaX e e e KX e e e MgX e e e FeX e e e As e e-008 C e e-002 Ca e e-004 Fe e e-015 K e e-004 Mg e e-005 Na e e-002 pH = Charge balance pe = Adjusted to redox equilibrium Activity of water = Ionic strength = e-002 Total alkalinity (eq/kg) = e-002 Total CO2 (mol/kg) = e-002 Electrical balance (eq) = e-003 Percent error, 100*(Cat-|An|)/(Cat+|An|) = Iterations = 12 Total H = e+002 Total O = e+001 OH e e H e e H2O e e As e-008 HAsO e e H2AsO e e AsO e e H3AsO e e C(-4) e-022 CH e e C(4) e-002 HCO e e CO e e NaHCO e e CO e e NaCO e e CaHCO e e MgHCO e e CaCO e e MgCO e e FeHCO e e FeCO e e Ca e-004 Ca e e CaOH e e Fe(2) e-015 Fe e e FeOH e e Fe(3) e-020 Fe(OH) e e Fe(OH) e e Fe(OH) e e FeOH e e Fe e e Fe2(OH) e e Fe3(OH) e e H(0) e-014 H e e K e-004 K e e KOH e e Mg e-005 Mg e e MgOH e e Na e-002 Na e e NaOH e e O e e CH4(g) CH4 CO2(g) CO2 Fe(OH)3(a) Fe(OH)3 Goethite FeOOH H2(g) H2 Hematite Fe2O3 O2(g) O2 Siderite FeCO3 Reading input data for simulation 9. Using exchange 1. Exchange assemblage after simulation 8. Using surface 1. Surface assemblage after simulation 8. Using pure phase assemblage 1. Pure-phase assemblage after simulation 8. Calcite e e e-003 Dolomite e e e-004 -2.336e-003 Surface charge, eq -1.252e-002 sigma, C/m**2 -4.408e-002 psi, V 1.716e F*psi/RT 5.560e+000 exp(-F*psi/RT) SurfOH e e SurfOH e e SurfO e e SurfOHAsO e e SurfHAsO e e SurfH2AsO e e NaX e e e CaX e e e KX e e e MgX e e e FeX e e e As e e-007 C e e-002 Ca e e-005 Fe e e-015 K e e-004 Mg e e-005 Na e e-002 pH = Charge balance pe = Adjusted to redox equilibrium Ionic strength = e-002 Total alkalinity (eq/kg) = e-002 Total CO2 (mol/kg) = e-002 Electrical balance (eq) = e-003 Percent error, 100*(Cat-|An|)/(Cat+|An|) = Total H = e+002 Total O = e+001 OH e e H e e H2O e e As e-007 HAsO e e H2AsO e e AsO e e H3AsO e e C(-4) e-023 CH e e C(4) e-002 HCO e e CO e e NaHCO e e CO e e NaCO e e CaCO e e CaHCO e e MgCO e e MgHCO e e FeCO e e FeHCO e e Ca e-005 Ca e e CaOH e e Fe(2) e-015 Fe e e FeOH e e Fe(3) e-019 Fe(OH) e e Fe(OH) e e Fe(OH) e e FeOH e e Fe e e Fe2(OH) e e Fe3(OH) e e H(0) e-014 H e e K e-004 K e e KOH e e Mg e-005 Mg e e MgOH e e Na e-002 Na e e NaOH e e O e e CH4(g) CH4 CO2(g) CO2 Fe(OH)3(a) Fe(OH)3 Goethite FeOOH H2(g) H2 Hematite Fe2O3 O2(g) O2 Siderite FeCO3 Reading input data for simulation 10. Using exchange 1. Exchange assemblage after simulation 9. Using surface 1. Surface assemblage after simulation 9. Using pure phase assemblage 1. Pure-phase assemblage after simulation 9. Calcite e e e-003 Dolomite e e e-004 -2.885e-003 Surface charge, eq -1.546e-002 sigma, C/m**2 -5.569e-002 psi, V 2.168e F*psi/RT 8.739e+000 exp(-F*psi/RT) SurfOH e e SurfOH e e SurfO e e SurfOHAsO e e SurfHAsO e e SurfH2AsO e e NaX e e e CaX e e e KX e e e MgX e e e FeX e e e As e e-006 C e e-003 Ca e e-005 Fe e e-016 K e e-004 Mg e e-005 Na e e-003 pH = Charge balance pe = Adjusted to redox equilibrium Ionic strength = e-002 Total alkalinity (eq/kg) = e-003 Total CO2 (mol/kg) = e-003 Electrical balance (eq) = e-004 Percent error, 100*(Cat-|An|)/(Cat+|An|) = Total H = e+002 Total O = e+001 OH e e H e e H2O e e As e-006 HAsO e e H2AsO e e AsO e e H3AsO e e C(-4) e-024 CH e e C(4) e-003 HCO e e CO e e NaCO e e NaHCO e e CO e e CaCO e e MgCO e e CaHCO e e MgHCO e e FeCO e e FeHCO e e Ca e-005 Ca e e CaOH e e Fe(2) e-016 Fe e e FeOH e e Fe(3) e-019 Fe(OH) e e Fe(OH) e e Fe(OH) e e FeOH e e Fe e e Fe2(OH) e e Fe3(OH) e e H(0) e-014 H e e K e-004 K e e KOH e e Mg e-005 Mg e e MgOH e e Na e-003 Na e e NaOH e e O e e CH4(g) CH4 CO2(g) CO2 Fe(OH)3(a) Fe(OH)3 Goethite FeOOH H2(g) H2 Hematite Fe2O3 O2(g) O2 Siderite FeCO3 Reading input data for simulation 11. End of run.
56
Kinetic Reactions RATES Datablock—defines rates of reaction as function of solution composition KINETICS Datablock Select rate expression(s) Amount of reactant Stoichiometry of reaction Parameters
57
Monod Kinetics Rate Definition Cell Growth
Parameter Value Vmax, 1/s 1e-5 KO2, mol/L X0, mol/L 0.4e-3
58
RATES Data Block See RATES in documentation for description of Basic statements
Biomass -start 5 REM Biomass is the name applied to this rate expression 10 vmax = 1e-5 20 KO2 = 1e-5 25 REM KIN returns current amount for kinetic reactant 30 X = KIN("Biomass") 35 REM MOL returns molality of species 40 O2 = MOL("O2") 50 rate = vmax * X * O2/(KO2 + O2) 55 REM TIME is internally defined time step for integration 60 moles = rate*TIME 70 save -moles -end RATES Biomass -start 5 REM Biomass is the name applied to this rate expression 10 vmax = 1e-5 20 KO2 = 1e-5 25 REM KIN returns current amount for kinetic reactant 30 X = KIN("Biomass") 35 REM MOL returns molality of species 40 O2 = MOL("O2") 50 rate = vmax * X * O2/(KO2 + O2) 55 REM TIME is internally defined time step for integration 60 moles = rate*TIME 70 save -moles -end
59
KINETICS Data Block CH2O + O2 = CO2 + H2O
Biomass -formula CH2O Sub 1 -m # moles -steps in 4 steps # seconds -tol 1e-8
60
Sign Conventions SAVE in RATES Coefficient in KINETICS
Kinetic reactant (KIN, M) Aqueous concentration + Decrease Increase -
61
Exercise Define a new element “Sub” with one species, Sub.
Start with water in equilibrium with atmospheric O2, 1 mmol/kgw Sub. Define a Monod kinetics with the parameters from the previous slides Initial amount of biomass is 4e-4 moles The stoichiometry of the reaction replaces Sub with CH2O Run the simulation for 1 day printing results every ¼ day. # biomass.pqi #Cell growth kinetics SOLUTION_MASTER_SPECIES Sub Sub 0 1 1 SOLUTION_SPECIES Sub = Sub log_k 0 SOLUTION 1 pH 7 Sub 1 O(0) 1 O2(g) -0.7 RATES Biomass -start 5 REM Biomass is the name applied to this rate expression 10 vmax = 1e-6 20 KO2 = 1e-5 25 REM KIN returns current amount for kinetic reactant 30 X = KIN("Biomass") 35 REM MOL returns molality of species 40 O2 = MOL("O2") 50 rate = vmax * X * O2/(KO2 + O2) 55 REM TIME is internally defined time step for integration 60 moles = rate*TIME 70 save -moles -end KINETICS 1 -formula CH2O -1 Sub 1 -m -m -tol e-008 -steps in 4 steps # seconds -step_divide 1 -runge_kutta 3 SELECTED_OUTPUT -file biomass.sel -reset false -time true -totals Sub O(0) C -kinetic_reactants Biomass
62
Kinetic Results Input file: H:\ntc\dk\phreeqc\biomass.pqi
Output file: H:\ntc\dk\phreeqc\biomass.pqo Database file: C:\Program Files\USGS\Phreeqc Interactive \phreeqc.dat Reading data base. SOLUTION_MASTER_SPECIES SOLUTION_SPECIES PHASES EXCHANGE_MASTER_SPECIES EXCHANGE_SPECIES SURFACE_MASTER_SPECIES SURFACE_SPECIES RATES END Reading input data for simulation 1. DATABASE C:\Program Files\USGS\Phreeqc Interactive \phreeqc.dat Sub Sub 0 1 1 Sub = Sub log_k 0 SOLUTION 1 pH 7 Sub 1 O(0) 1 O2(g) -0.7 Biomass start 5 REM Biomass is the name applied to this rate expression 10 vmax = 1e-6 20 KO2 = 1e-5 25 REM KIN returns current amount for kinetic reactant 30 X = KIN("Biomass") 35 REM MOL returns molality of species 40 O2 = MOL("O2") 50 rate = vmax * X * O2/(KO2 + O2) 55 REM TIME is internally defined time step for integration 60 moles = rate*TIME 70 save -moles end KINETICS 1 formula CH2O -1 Sub 1 m m tol e-008 steps in 4 steps # seconds step_divide 1 runge_kutta 3 SELECTED_OUTPUT file biomass.sel reset false time true totals Sub O(0) C kinetic_reactants Biomass Beginning of initial solution calculations. Initial solution 1. Solution composition Elements Molality Moles O(0) e e-004 Equilibrium with O2(g) Sub e e-003 Description of solution pH = pe = Activity of water = Ionic strength = e-007 Mass of water (kg) = e+000 Total alkalinity (eq/kg) = e-010 Total carbon (mol/kg) = e+000 Total CO2 (mol/kg) = e+000 Temperature (deg C) = Electrical balance (eq) = e-010 Percent error, 100*(Cat-|An|)/(Cat+|An|) = Iterations = 4 Total H = e+002 Total O = e+001 Redox couples Redox couple pe Eh (volts) O(-2)/O(0) Distribution of species Log Log Log Species Molality Activity Molality Activity Gamma OH e e H e e H2O e e H(0) e-025 H e e O(0) e-004 O e e Sub e-003 Sub e e Saturation indices Phase SI log IAP log KT H2(g) H2 H2O(g) H2O O2(g) O2 Beginning of batch-reaction calculations. Reaction step 1. Using solution 1. Using kinetics 1. Kinetics defined in simulation 1. Kinetics 1. Kinetics defined in simulation 1. Time step: seconds Rate name Delta Moles Total Moles Reactant Coefficient Biomass e e CH2O Sub C e e-006 Sub e e-004 pH = Charge balance pe = Adjusted to redox equilibrium Ionic strength = e-006 Total CO2 (mol/kg) = e-006 Percent error, 100*(Cat-|An|)/(Cat+|An|) = Iterations = 55 Total H = e+002 Total O = e+001 H e e OH e e C(-4) e+000 CH e e C(4) e-006 CO e e HCO e e CO e e H(0) e+000 H e e O(0) e-004 O e e Sub e-004 Sub e e CH4(g) CH4 CO2(g) CO2 H2(g) H2 O2(g) O2 Reaction step 2. Time step: seconds Biomass e e CH2O C e e-005 Sub e e-004 pH = Charge balance pe = Adjusted to redox equilibrium Ionic strength = e-006 Total CO2 (mol/kg) = e-005 Total O = e+001 H e e OH e e CH e e C(4) e-005 CO e e HCO e e CO e e H e e O(0) e-004 O e e Sub e-004 Sub e e CH4(g) CH4 CO2(g) CO2 H2(g) H2 O2(g) O2 Reaction step 3. Time step: seconds Biomass e e CH2O C e e-005 Sub e e-004 pH = Charge balance pe = Adjusted to redox equilibrium Ionic strength = e-006 Total CO2 (mol/kg) = e-005 H e e OH e e CH e e C(4) e-005 CO e e HCO e e CO e e H e e O(0) e-004 O e e Sub e-004 Sub e e CH4(g) CH4 CO2(g) CO2 H2(g) H2 O2(g) O2 Reaction step 4. Time step: seconds Biomass e e CH2O C e e-005 Sub e e-004 pH = Charge balance pe = Adjusted to redox equilibrium Ionic strength = e-006 Total CO2 (mol/kg) = e-005 Total O = e+001 H e e OH e e CH e e C(4) e-005 CO e e HCO e e CO e e H e e O(0) e-004 O e e Sub e-004 Sub e e CH4(g) CH4 CO2(g) CO2 H2(g) H2 O2(g) O2 End of simulation. Reading input data for simulation 2. End of run.
63
PHREEQC Reactants Type and number are used to define PHAST reactions
Keyword data blocks define reactants SOLUTION—Solutions EQUILIBRIUM_PHASES—Equilibrium minerals and gases EXCHANGE—Exchangers SURFACE—Surfaces KINETICS and RATES—Kinetic reactions SOLID_SOLUTIONS—Solid solutions GAS_PHASE—gas bubble (rarely used) Store reactants on shelves by type and number Put reactants together to define a reaction calculation SAVE/USE reactants Type and number are used to define PHAST reactions
Similar presentations
![Karst Chemistry I. Definitions of concentration units Molality m = moles of solute per kilogram of solvent Molarity [x]= moles of solute per kilogram.](/14/4335485/big_thumb.jpg "Karst Chemistry I. Definitions of concentration units Molality m = moles of solute per kilogram of solvent Molarity [x]= moles of solute per kilogram.>")
