scholarly journals Thermodynamic equilibria of tailings dump pond water of Sherlovaya Gora tin-polymetallic deposit (Transbaikalia)

2019 ◽  
Vol 98 ◽  
pp. 01014
Author(s):  
Oleg Eremin ◽  
Olga Rusal ◽  
Maria Solodukhina ◽  
Ekaterina Epova ◽  
Georgy Yurgenson
Keyword(s):  
Free Energy ◽  
Energy Minimization ◽  
Total Pressure ◽  
Toxic Elements ◽  
Pond Water ◽  
Minimization Algorithm ◽  
Program Complex ◽  
Potential Toxic Elements ◽  
Polymetallic Deposit ◽  
Gibbs Free Energy Minimization

The potential toxic elements (Be, U, As, Cd, Pb, Sb, Bi) were detected for mine landscape of Sherlovaya Gora tin-polymetallic deposit. Thermodynamic calculation of equilibrium for tailings dump pond water was carried out by means of “Selektor” program complex based on Gibbs free energy minimization algorithm at 25°C and 1 bar total pressure. It turned out that the mine water is supersaturated with respect to many sulphates of Ca, Mg, Sr, Zn, K, Cu, Ni, Cd, Be, Al, Ce and Y, fluorides of (Ln and Y, Sc), and Y phosphate.

Direct Energy Minimization Algorithm for Numerical Simulation of Carbon Dioxide Injection

2021 ◽  
Author(s):  
Lyudmila Khakimova ◽  
Anna Isaeva ◽  
Vladimir Dobrozhanskiy ◽  
Yury Podladchikov
Keyword(s):  
Carbon Dioxide ◽  
Numerical Simulation ◽  
Free Energy ◽  
Phase Equilibria ◽  
Energy Minimization ◽  
Multicomponent System ◽  
Ternary Mixtures ◽  
Minimization Algorithm ◽  
Carbon Dioxide Injection ◽  
Three Phase

Abstract We discuss numerical simulation of carbon dioxide injection considered by oil and gas companies. Complex behavior of multicomponent reservoir fluids mixed with carbon dioxide may cause the occurrence of vapor-liquid-liquid equilibria (VLLE), salt precipitation in aquifers, pore-clogging, etc. We propose a simple algorithm for phase equilibria calculations based on the minimization of the multicomponent system free energy. This algorithm can be used to calculate phase separations and component partitioning between the phases under various conditions (critical region, two- and three-phase equilibria, etc.). We demonstrate the applicability of the proposed algorithm in a series of calculations. We consider binary and ternary mixtures that include carbon dioxide and hydrocarbons. We examine the algorithm in two- and three-phase equilibrium calculations and compare its performance with the popular iterative fugacity equilibration technique. We show that both calculation techniques give near-identical results for the considered mixtures. Thus, we show that the free energy minimization algorithm can be used interchangeably with the fugacity equilibration technique for calculating phase equilibria. This algorithm is applicable for VLLE calculations, which is important when considering multicomponent reservoir fluids that include carbon dioxide.

Sign in / Sign up

Export Citation Format

Share Document