Method for manufacturing building material by carbonizing silicon-calcium slag

The invention discloses a method for manufacturing a building material by carbonizing silicon-calcium slag, which comprises the following steps of: in the process of extracting aluminum oxide from fly ash, washing the dissolved silicon-calcium slag, drying the silicon-calcium slag by high-temperature flue gas at a kiln head, cooling the dried silicon-calcium slag to normal temperature, adding water, blending, uniformly stirring, and feeding into a pressurizing forming machine to manufacture various building profiles. The building profile is subjected to carbonization treatment after being manufactured and formed. The content of gamma-dicalcium silicate in the tailings-calcium silicate slag obtained in the process of extracting aluminum oxide from fly ash by using a limestone sintering method is high, and meanwhile, the gamma-dicalcium silicate has the characteristic of good air hardness, so that the strength of the finished product can be greatly improved after the product is cured by carbon dioxide under a c