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This presentation discusses the COSIA Beyond Solubility project, which aims to develop simplified models and conduct flowsheet simulations for kinetics and surface complexation. The focus is on modeling the adsorption of SiO2 on MagOx using the Double Layer Model.
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COSIA beyond solubilityproject meeting OLI Systems, Inc. 4 December 2018
Project introduction COSIA beyond solubility • Meet these objectives by • Simplified model development in kinetics and surface complexation • Flowsheet simulations developed in OLI Flowsheet: ESP
Project accommodations Cost Intellectual Property Organization Timing
Today’s plan Modeling phase discussion Tuning discussion Deployment discussion
Modeling Adsorption of SiO2 on MagOxwith Surface Complexation Double Layer Model • Protonation/deprotonation of surface on minerals: (i.e. XOH0 = MagOx) • XOH0 + H3O+ = XOH2+ + H2O K+int = • XOH0 + H2O = XO- + H3O+K-int= • Surface complexation with SiO2: • XO- + HSiO3- + H3O+ = XO-SiO2- + 2H2O K1int = • XOH0 + HSiO3- + H3O+ = XOH-SiO20 + 2H2O K2int= • XOH2+ + HSiO3- + H3O+ = XOH2-SiO2+ + 2H2O K3int = Surface acidity constants axs(aH3Os, aHSiO3s): activities of species at the surface, which are related to bulk solution activities, axb, by axs=axb·[exp(-F/RT)]z where is surface potential F is Faraday constant z is charge of the ion adsorption binding constants • Key parameters in DLM: • K+int & K-int – based on acidimetric titration data & constrained by PZC • K1int - K3int – based on adsorption data axb – determined by MSE thermodynamic model – calculated from DLM, as is related to surface charge density, , by = (8·R·TK··0·I·103)1/2·sinh[Z· ·F/(2·R·T)] can be determined from =F·(zi·Ci)/(A·S) A – specific surface area, m2/g S – solid concentration, g/kgH2O Ci – concentration (mol//kgH2O) of complex species
Demonstration of Results • Coverage of experimental conditions - • Temperature: 10 to 100C • MagOx concentration used: 0 to 20,000ppm • SiO2 concentration treated: 7 to 260 ppm • Solution pH range: 6.3 to 11.5