The invention relates to a comprehensive treatment technology of waste aluminum ash, and concretely relates to processes for producing aluminum hydroxide from the waste aluminum ash, producing refractory materials through utilizing waste residues, and producing ammonium chloride through utilizing wastewater and an exhaust gas. The technology is characterized in that a sodium aluminate solution and a plaster are generated through dissolving out the aluminum ash by a cycle alkaline solution having a high concentration Na2Ok 220g/l at a temperature of above 260DEG C under a pressure of above 60kg/cm<3>; the aluminum ash is washed with water to remove most chlorides before the dissolving-out of the aluminum ash by the cycle alkali solution, and the obtained washing solution is used for absorbing ammonia generated in the dissolving-out process; and the plaster generated by the aluminum ash is used for producing refractory bricks or castable materials. A large amount of ammonia is contained in the waste aluminum ash, and ammonium chloride is prepared through recovering the ammonia with a salt washing solution in a cycle mode, so the ammonia pollution is eliminated, and products are prepared from the ammonia. The sodium aluminate solution undergoes crystal seed decomposition to generate an aluminum hydroxide fire retardant and a decomposition mother solution, and the aluminum ash is dissolved after the decomposition mother solution evaporates.