Microstructure Parameter Estimation in Permeability Calculation of Well Cement during Early Hydration by a Simple Particle Expansion Model

Abstract— The inter-connected pores of cement after displaced
into wellbore is believed to contribute for fluids migration. It
cannot be accurately evaluated using the present sonic and
acoustic methods due to its density based principles.
Impedance technique is applied at elevated temperature and
pressure for its pores characterization. A simple particle
expansion model is proposed to solve the microstructural
parameters (surface and volume of pores) in the unsetting
cement that was previously encountered. The proposed model
is validated by comparing the trend lines of cement prior to
(our model) and after (measurement) setting. The results are
employed in the Katz-Thompson equation for estimating its
permeability. A comparable result of permeability calculation to the measured data is fairly observed.

Keywords-component; well cement; elevated temperature;
impedance technique; particle expansion model