METHOD OF OIL STRATUM CRITICAL ZONE TREATMENT

摘要

FIELD: oil-extracting industry. SUBSTANCE: before oil stratum treatment they determine perforated thickness of oil stratum and its operative part and number of cycles, required to open oil stratum inoperative part. Then required amount of acid and blocking composition is determined. Volume of portions of each following cycle is to be by 10 - 50 % less, than previous one. Volume of blocking composition of the last cycle is to be no less, than volume of borehole section in zone of operative oil stratum and as optimal choice - to be equal to the volume. The terms are required to press all volume of acid into oil stratum, that prevents operational string metal corrosion during reaction and increases depth of acid penetration in oil stratum. From cycle to cycle they increase pressure of pumping in blocking composition and last portion of blocking composition is pumped in under operational string extreme tolerable pressure. In process of exploitation of oil stratum blocking composition, that has hydrocarbon in its outer phase, is easily washed away by borehole liquid. Blocking composition squeezes solution of waste acid out of crack into pores of stratum. Globules sizes of blocking composition dispersing phase are bigger, that stratum pores sizes, so blocking composition is not capable to enter the pores. Optimal condition is equal volumes of acid and blocking composition in one portion. During one cycle 3 - 5 m of oil stratum thickness is opened. EFFECT: increased efficiency of operating oil stratum treatment.