CALCITE POWDER DEFORMATION IN THE PRESENCE OF AQUEOUS SOLUTIONS OF VARIOUS COMPOSITION

Abstract

The rates of calcite powder compaction under uniaxial stress in CaCO3 saturated aqueous solutions containing magnesium cations or humate anions have been compared with computed rate estimations. The interplay of calcite solubility, dissolution kinetics, and mass transfer rate of solid matter through the liquid bulk controls the overall process kinetics. A not significant difference between the experimental and calculated datasets (within 20%) confirms the adequacy of the model proposed. The calcite creep rate in magnesium-containing media is limited by the material dissolution stage as a result of the surface dolomitization. The creep hindering by humate anions is likely to be due to the partial surface coverage with adsorbed matter.

Keywords

• pressure solution
• kinetic and diffusive regime of deformation
• solubility
• dissolution rate. liquid interlayers
• diffusion coefficient