Method for preparing autoclaved fly ash brick through hydration with PO saponification waste residue, garbage power plant slag and coal-fired power plant fly ash

The invention discloses a method for preparing an autoclaved fly ash brick through hydration with PO saponification waste residue, garbage power plant slag and coal-fired power plant fly ash. The method is characterized in comprising the following steps: (1) 100g of concrete is prepared into a building block with a size of 70mm*50mm*20mm; (2) garbage power plant slag is crushed; slag particles with sizes of 2-3mm are selected as an aggregate of the concrete; (3) water is added for dissolving additive auxiliary materials including an activating agent Na2SiO3, early strength agents Na2SO4 and triethanolamine, and a dispersing agent sodium rosinate; the PO saponification waste residue is added; the garbage power plant slag, PO42.5 cement and coal-fired power plant fly ash are sequentially added; the mixture is well mixed, such that a slurry is prepared; (4) the slurry obtained in the step (3) is fetched and pressed into building blocks; (5) the building blocks obtained in the step (4) are allowed to stand for cu