Preparation method of low-cost fireproof heat-insulating aerogel felt

The invention discloses a preparation method of a low-cost fireproof heat-insulation aerogel felt, which comprises the following steps: directly compounding aerogel powder and a glass fiber felt into an aerogel felt, roller-coating a dense fireproof flame-retardant layer on an aerogel layer by adopting a roller-coating process, spraying a hydrophobic modification reagent on the fireproof flame-retardant layer by adopting a spraying process, and drying to obtain the low-cost fireproof heat-insulation aerogel felt. Wherein the selected inorganic metal flame-retardant filler can still be used after combustion, and when the proportion of the inorganic metal flame-retardant filler to the flame retardant is optimized, the inorganic metal flame-retardant filler and the flame retardant can permeate into the heat insulation layer, the layering phenomenon of the heat insulation layer and the flame-retardant layer after curing is avoided, and the tensile strength is enhanced; therefore, the aerogel powder in the heat in