▎ 摘　　要

NOVELTY - Foam drainage agent comprises 2-4 wt.% intermediate A, 43-47 wt.% modified cocamidopropyl betaine, 18-22 wt.% cocamidopropylamine oxide, 1.5-2.5 wt.% perfluorosurfactant, 13-17 wt.% phosphoric acid, 4-6 wt.% aldehyde ketone amine condensate, and water (remaining amount). USE - Used as foam drainage agent. ADVANTAGE - The agent: solves the technical problems that the existing foam drainage agent has poor well purifying ability and water-unlocking ability; and can adapt to the high condensation oil, high salinity and high temperature of gas field produced water. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing the foam drainage agent comprising adding water at room temperature, then adding ABS, and stirring and dissolving uniformly, then adding benzalkonium chloride and stirring to form intermediate A, adding modified cocamidopropyl betaine, cocamidopropyl amine oxide, perfluorosurfactant and water, stirring and mixing uniformly according to intermediate A, continuously adding phosphoric acid and aldehyde ketone amine condensate into reaction kettle, and uniformly stirring to obtain the finished product.