THERMAL PROPERTIES OF HEAVY OIL SATURATED RESERVOIR ROCKS BEFORE AND AFTER HIGH TEMPERATURES TREATMENT

Abstract

This paper aims to study of the variation of key thermal properties (thermal diffusivity, heat capacity, and derived values of thermal conductivity) of heavy oil saturated reservoir rock sample before and after high temperature treatment. A laser flash method (LFA 457) and differential scanning calorimeter (DSC 204 F1) were employed to study of the temperature effect on the thermal diffusivity ( ) and heat capacity ( ) of natural heavy oil reservoir rock sample. The measurements of the thermal – diffusivity have been made over the temperature range from (296 to 1023) K. The isobaric heat capacities of the same sample were measured in the temperature range from (299 to 768) K. Uncertainties of the measurements are 3 % and 1 % for and , respectively. The measurements were made in heating and cooling runs. Significant difference between the measured properties before and after thermal treatment was observed. Measured values of thermal diffusivity ( ) and heat capacity ( ) together with density data ( ) were used to calculate the derived very important properties of rock sample (thermal conductivities, ) using well-known thermodynamic relation, . A relationship between the temperature behavior of the thermophysical properties ( , , ) and the physical-chemical processes (thermal decomposition of pore heavy oil and volatilization of residual water absorbed in the pore walls) occurring in the rock pores during heating in distinct temperature ranges has been studied. The sig-nificant effect of thermal decomposition and dehydration processes on the temperature behavior of measured values of thermal -diffusivity and heat-capacity of oilbearing reservoir rock sample at high temperatures (above 680 K) was experimentally observed.