Method for manufacturing porous steam-cured phosphorus removal biological filter material by using ester-hardened sodium silicate casting waste sand

The invention belongs to the technical field of resource recycling and reusing, and particularly relates to a method for manufacturing a porous steam-cured phosphorus removal biological filter material by using ester-hardened sodium silicate casting waste sand, which comprises the following steps: (1) mechanically crushing ester-hardened sodium silicate waste sand blocks; (2) adding a certain amount of high-temperature acidic water into the crushed waste sand, rubbing/washing for multiple times by using a sand washer, and regulating the pH value of the wastewater by using an alkaline substance for later use; (3) the washed sand is subjected to ball milling and sieving; (4) uniformly mixing the sieved waste sand powder, cement, lime, fly ash, gypsum and the like for later use; (5) adding a pore-forming agent in proportion, and uniformly stirring to obtain a premix; (6) adding the standby wastewater produced in the step (2) into the premix, stirring, and preparing raw material pellets with a certain size by usi