The role of physical and chemical processes of silica scale growth in geothermal wells

Abstract

Silica scaling remains to be a major restriction for geothermal heat extraction. Our goal is to construct the model reproducing the real silica scaling. To meet this goal, we develop the multi-scale modeling of silica scale growth and compare the simulation result of the amount and the distribution of silica deposition and the data from a laboratory or a field experiment to verify our model. In meso-scale model, the adhesion of the colloidal silica is analyzed using Lagrangian method, while, in the macro-scale model, lattice Boltzmann (LB) simulation is performed using the scale growth rate obtained at the meso-scale model. From our simulation result, the real phenomenon is reproduced quantitatively and quantitatively, which has not been reproduced in the reaction kinetics. It is, therefore, necessary to emphasize the adhesion of the colloidal silica should be taken into account for reproducing silica scaling.