• Corpus ID: 231632223

PyEquIon: A Python Package For Automatic Speciation Calculations of Aqueous Electrolyte Solutions

@inproceedings{Marcellos2021PyEquIonAP,
  title={PyEquIon: A Python Package For Automatic Speciation Calculations of Aqueous Electrolyte Solutions},
  author={Caio Felippe Curitiba Marcellos and Gerson Dias da Silva J{\'u}nior and Elvis do A. Soares and Fabio Ramos and Amaro Gomes Barreto},
  year={2021}
}

• C. Marcellos, Gerson Dias da Silva Júnior, +2 authors A. G. Barreto
• Published 18 January 2021
• Chemistry

In several industrial applications, such as crystallization, pollution control, and flow assurance, an accurate understanding of the aqueous electrolyte solutions is crucial. Electrolyte equilibrium calculation contributes with the design and optimization of processes by providing important information, such as species concentration, solution pH and potential for solid formation. In this work, a pure Python library distributed under BSD-3 license was developed for the calculation of aqueous electrolyte equilibrium. The package takes as inputs the feed components of a given solution, and it automatically identifies its composing ions and the chemical reactions involved to calculate equilibrium conditions. Moreover, there is no established electrolyte activity coefficient model for a broad range of operational conditions. Hence, in this package, built-in activity coefficient models are structured in a modular approach, so that the non-ideality calculation can be performed by a user provided function, which allows further research in the topic. The package can be used by researchers to readily identify the equilibrium reactions and possible solid phases in a user friendly language. Nature of problem: Calculation of aqueous electrolyte equilibrium in a pure python package with code exportation for embedding in dynamic simulations. Solution method: A recursive algorithm identifies the system reactions and chemical species. Possible candidates of solid phases are also identified. The equilibrium equations are defined based on a database of reactions and associating the involved species. The nonlinear system is composed of the equilibrium equations, charge balance, mass balances and optionally gaseous carbon dioxide equilibrium or pH. Activity coefficient models, such as Debye-H¨uckel and Pitzer, are used based on a database containing its parameters. The nonlinear system is solved with a Newton-Raphson method. The software allows automatic jacobian generation and code exportation for incorporation in differential algebraic equations.