ACIDIC COMPOSITION FOR TREATING FACE-ADJACENT BED SECTION Russian patent published in 2004 - IPC

FIELD: oil extractive industry.

SUBSTANCE: acidic composition for treating face-adjacent section of bed includes concentrated hydrochloric acid or mixture of concentrated hydrochloric, hydrofluoric and waterless oxiethylenediphosphone acids and mixture of polar organic dissolvent and non-polar aromatic hydrocarbon dissolvent - toluene, contains as said polar dissolvent isopropylene spirits, isopropylene spirits and toluene are taken at volume ratio of 3:1-2, amount of concentrated hydrochloric acid or mixture of concentrated hydrochloric, hydrofluoric and waterless oxyethylenediphosphone acids taken at mass ratio 15:2:1, being at 5-35 percents of mass.

EFFECT: acidic composition for treating face-adjacent section of force-pumping and extractive wells, having low chemical activity towards metal and cement stone before mixture with water, but having high dissolving capability towards asphalt-resin-paraffin deposits, and while being pumped into bed and contacting bed water capable of conversion into composition with high chemical activity also towards iron sulfide, argillaceous particles, calcium hydroxides, magnesium hydroxides, and hydroxides of other particles of hard phase lowering filtering characteristics of bed.

2 tbl, 1 dwg