MULTIFUNCTIONAL ACID COMPOSITION FOR TREATMENT OF BOTTOMHOLE FORMATION ZONE AND METHOD OF ACID TREATMENT FOR BOTTOMHOLE FORMATION ZONE Russian patent published in 2016 - IPC C09K8/74 E21B43/27 

FIELD: oil and gas industry.

SUBSTANCE: inventions group relates to oil and gas industry. Multifunctional acid composition for treatment of the formation bottomhole zone contains the following elements in wt %: hydrochloric acid (in terms of HCl) 1.0-24.0; demulsifier 0.2-1.5; corrosion inhibitor 0.002-3.0; stannous or copper chloride or CA-2000-M, or SCA-90-M, or ascorbic acid 0.2-5.0; water - the remaining share. The method of acid treatment for bottomhole zone of the formation with permeability of 0.5-400 mD includes injection into the well of the above acid composition in volume of 0.1-4.0 m³ per running metre of perforated thickness of the formation with further flushing into the formation, process withhold and removal of reaction products.

EFFECT: compatibility of the composition for formation treatment with formation fluids, inhibiting of acid corrosion, formation of emulsions and resin formation.

11 cl, 5 tbl, 49 ex