The performance of systematically substituted temporary clay stabilizers has significant correlation with performances predicted by computational modeling. The model binding energies of different clay stabilizers onto various bentonite crystalline faces were independently calculated and corresponded well with a standard bench-top performance method indicating a systematic approach in the development of temporary clay stabilization performance may be realized.

Various clay stabilizers are employed when stimulation requiring aqueous based fluids is necessary in water sensitive formations. Typically, if swelling or migrating clays are present, temporary or permanent stabilizers are utilized. Low molecular weight temporary stabilizers as a rule perform above a critical level concentration, but as the stabilizers concentration diminishes in the fracturing fluid due to flowback, formation fluid displacement, or other mechanisms, the clay can swell reducing porosity and permeability. Permanent stabilizers are generally higher molecular weight and can adhere to single or multiple clay platelets thus dissolution of the stabilizer into the fluid is not favored and the beneficial anti-swell effect is of higher duration. It was discovered when using binding energies of substituted ammonium ions on a bentonite interlayer, the binding energies correlated well with performance testing.

The binding energy of ammonium ions substituted with 0 to 4 methyl groups or choline were calculated on the 001 crystal face(s) of bentonite. Bentonite being a 2:1 swelling clay had its inter-crystalline space gapped at 8 to 20Å. Unique molecular ions were introduced to this space and the binding energies were calculated using a Monte Carlo Isothermal Adsorption method. Performance testing was then conducted using a low pressure Bariod fluid loss cell. A set concentration of sodium bentonite was blended into water a specific RPM and duration in the presence of the particular ammonium ion, placed in the cell and pressure was applied and leak off rate were measured. The resulting leak off rates were compared to the binding energy.

The design of efficient temporary clay stabilizers can be directly linked to performance. Further, the duration of the stabilization may also be modeled in a way where experimentation would be difficult in flow through porous media.

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