Antifreezing foaming agent and preparation method thereof

The invention belongs to the technical field of oil-gas field chemical industry, and particularly relates to an antifreezing foaming agent. The antifreezing foaming agent is prepared from the following raw materials in percentage by mass: 30-50% of lauramido propyl amine oxide, 10-30% of dodecyl dimethyl betaine, 0.3-0.8% of polyvinylpyrrolidone, 15-25% of sodium chloride, 5-15% of ethylene glycol and 5-15% of water. The invention also relates to a preparation method of the antifreezing foaming agent, which comprises the following steps: sequentially adding formula amounts of lauramido propyl amine oxide, dodecyl dimethyl betaine, polyvinylpyrrolidone, sodium chloride and ethylene glycol into 5-15 wt% water while stirring, and completely dissolving. After being added into the water-producing gas well, the antifreezing foaming agent has the advantages of high foaming capacity, high foam stability and high liquid carrying capacity; the foaming effect is not influenced in the low-temperature environment in winter; no other antifreezing assistant is needed in the injection process; and the antifreezing foaming agent is suitable for condensate-oil-containing gas wells with high water production rate.