SOLID BASE OF COMPOSITION FOR ACID TREATMENT OF CRITICAL AREA OF FORMATION Russian patent published in 2005 - IPC

FIELD: oil and gas production.

SUBSTANCE: solid base 75.0-95.0% nitric acid-urea reaction products serving as acid reagent, 1.0-5.5% tertiary amines-hydrogen peroxide reaction product, 2.5-15.0% organic derivatives of phosphonic acid, e.g. nitrilotrimethylphosphonic acid or oxyethylidenephosphonic acid, and 1.5-4.5% nitrogen-containing corrosion inhibitor. Composition prepared on proposed base is more efficient owing to widened application area of composition including wells with formation temperature up to 100°C, successfully prevented, under these conditions, formation of stable oil emulsions with elevated iron-containing stabilizers level, removed water-oil emulsions from critical area of formation, preserved low corrosion activity, and excluded loss in active properties of base upon storage and transportation.

EFFECT: improved performance characteristics of formation critical area composition.

2 cl, 3 tbl