Seawater system
Multi-phase and multi-species equilibria of seawater
including H+,Na+,Ca2+,Mg2+,OH-,Cl-, CO32-,HCO3-,SO42-,CO2(aq),CO2(g), CaCO3(s),CaSO4(s) and CaSO4·2H2O(s)
In this section, you can calculate the properties and speciation of seawater at temperature from 0 to 250 °C, pressure from 1 to 1000 bar, and salinity from 0 to 105 ‰.
In this section, you can vary the concentrations of individual ions in seawater, instead of salinity, to investigate their influence on the properties and speciation of seawater
at temperature from 0 to 250 °C, pressure from 1 to 1000 bar. The concentration of these ions can be freely adjusted within the ranges corresponding to seawater salinities of 0 to 105 ‰,
which is, Na+ 0 to 1.5 mol/kg, Mg2+ 0 to 0.15 mol/kg, SO42- 0 to 0.09 mol/kg, and Cl- is automatically adjusted to maintain charge balance.
In this section, you can calculate the properties and speciation of the CO2–CaCO3–NaCl–H2O system,
which is often regarded as a simplified seawater system, at temperature from 0 to 250 °C, pressure from 1 to 1000 bar, and NaCl concentration from 0 to 6 mol/kg.
Results
| Initial condition | ||
| Temperature: | K | |
| Pressure: | bar | |
| Total CO2: | mol/kg | |
| Salinity: | ‰ | |
| Total CaCO3: | mol/kg | |
| Properties of aqueous solution | ||
| pH: | ||
| Ionic strength: | mol/kg | |
| Speciation equilibrium in aqueous solution | ||
| concentration (m) mol/kg | activity coefficient (γ) | |
| H+: | ||
| OH-: | ||
| Na+: | ||
| K+: | ||
| Ca2+: | ||
| Mg2+: | ||
| Cl-: | ||
| SO42-: | ||
| HCO3-: | ||
| CO32-: | ||
| CO2(aq): | ||
| CaOH+: | ||
| CaCl+: | ||
| CaCO30: | ||
| CaSO40: | ||
| MgCO30: | ||
| MgSO40: | ||
| Distribution of major species | ||
| CO2-related phases | ||
| CO2(g): | ||
| CO2(l): | ||
| CO2 hydrate(s): | ||
| Mineral phases | ||
| Mineral | Apparent solubility product (Ksp′) | Saturation state |
| Calcite: | ||
| Aragonite: | ||
| Gypsum: | ||
| Anhydrite: | ||
References
[1] Sun, H., Duan, Z., Jiang, L.,(in prep.)