The testing technique of the hydrochloric acid treatment efficiency for reservoir rocks (on the example of low-permian deposits of the Dnieper-Donetsk depresion)

Abstract

On the example of reservoir rocks of low-permian deposits Hnidyntsivske in the oil field Dnieper-Donets basin
there was found out that the effect of polymer-clay drilling mud results in 4.2 times reduction of the phase
permeability. Using the proposed technique the testing of the effectiveness of 14% hydrochloric acid solution was
done. The most effective one was revealed to be a treatment of reservoir rocks where filtrate and free oil were displaced
from the pore volume. During the process the phase permeability increases in more than 13 times compared
with the initial one. The described technique considers the lithologic and petrophysical features of reservoir rocks
and can be used successfully in productive deposits with other geological and technical conditions of occurrence. It
has been proved that the presence of the filtrate and hydrocarbons in pore volume does not enable to increase the
efficiency of hydrochloric acid treatment in formation bottomhole zone.