H.Kalka Aqion

H.Kalka Aqion is a powerful aqueous geochemistry software program for water chemistry analysis – including speciation, saturation indices, pH and alkalinity calculations, redox modeling, and mixing/titration simulations. Developed by H. Kalka, Aqion is widely used by hydrogeologists, environmental engineers, and water quality specialists to interpret chemical analyses of groundwater, drinking water, surface water, and industrial water samples. Version 8.8.5 continues the software’s mission of providing rigorous, easy-to-use geochemical modeling tools to professionals and students alike. Whether identifying which chemical forms (free ions, complexes) dominate in a solution, determining if minerals are undersaturated (will dissolve) or oversaturated (will precipitate), or simulating mixing of waters with different chemistries, Aqion delivers the accuracy and insight that water chemistry investigations demand.

???? Primary Users

This professional aqueous geochemistry software is designed for:

  • Hydrogeologists & Geochemists analyzing water chemistry, speciation, and mineral equilibrium in groundwater and surface water.

  • Environmental Scientists & Engineers assessing water quality, contaminant fate, and geochemical reactions.

  • Water Treatment & Utilities Professionals evaluating drinking water stability, corrosion potential, and scaling tendencies.

  • Academic Researchers & Educators teaching and applying geochemical modeling in hydrogeology courses.

  • Mining & Industrial Process Engineers predicting acid mine drainage, sulfide oxidation, and heavy metal mobility.

⚡ Key Features & Capabilities

???? Speciation Analysis

Chemical Form Calculation:

  • Free ions (Ca²⁺, Mg²⁺, Na⁺, K⁺, Fe²⁺, Fe³⁺, etc.)

  • Inorganic complexes (CaSO₄⁰, FeHCO₃⁺, Al(OH)₄⁻, etc.)

  • Organic complexes (with dissolved organic matter – DOC)

  • Trace metals speciation (Cu, Zn, Pb, Cd, Ni, etc.)

  • Redox species (Fe²⁺/Fe³⁺, As(III)/As(V), Cr(III)/Cr(VI), S(-II)/S(VI))

Activity Coefficients:

  • Debye-Hückel, Davies, or specific ion interaction theory (SIT)

  • Ionic strength correction for high-salinity brines

???? Saturation Indices (SI)

Mineral Equilibrium:

  • SI = log(IAP / K) – undersaturated (SI < 0), equilibrium (SI = 0), supersaturated (SI > 0)

  • Common minerals: calcite, dolomite, gypsum, anhydrite, halite, quartz, amorphous silica, Fe‑oxides, Mn‑oxides, clay minerals

Application:

  • Predict scaling (CaCO₃, CaSO₄) in pipes, boilers, geothermal systems

  • Assess corrosion potential (aggressive CO₂, low hardness)

⚖️ pH & Alkalinity Calculations

  • Charge balance error (CBE) for analysis validation (typically < 5%)

  • Alkalinity as HCO₃⁻, CO₃²⁻, OH⁻ (titration to pH 4.5)

  • pH from specified CO₂ partial pressure or from alkalinity + DIC

⚡ Redox Reactions & pe/pH Diagrams

Redox Couples:

  • Fe²⁺/Fe³⁺, S(-II)/S(VI), N(-III)/N(V), As(III)/As(V), Cr(III)/Cr(VI)

  • pe (electron activity) from measured redox potential (Eh) or from dissolved O₂

Applications:

  • Acid mine drainage (pyrite oxidation)

  • Arsenic mobilization in reducing aquifers

  • Denitrification / nitrate reduction

???? Mixing & Titration Simulations

  • Mix two waters (e.g., groundwater + seawater, river + wastewater) – compute resulting species and saturation

  • Titrate with acid or base (HCl, NaOH, H₂SO₄)

  • CO₂ degassing / uptake

???? What’s New in Version 8.8.5

  • New Mineral Database – 50+ additional phases (carbonates, sulfates, clays, Fe/Al oxyhydroxides)

  • Pitzer Activity Model – For high ionic strength brines (up to 6 molal)

  • Redox Kinetics Module – Time‑dependent pyrite oxidation, denitrification half‑life

  • Batch Mode (CSV) – Process 100+ samples in one run (report SI, speciation, charge balance)

  • Export to PHREEQC – Convert Aqion project to PHREEQC input file (.phr)

  • Multi‑language GUI – English, German, Spanish, French

???? System Requirements

Minimum Requirements

  • OS: Windows 10/11 (64-bit)

  • CPU: Intel Core i5 or equivalent

  • RAM: 4 GB

  • Storage: 500 MB free space

  • Display: 1024 × 768 resolution