Method of making waterproof magnesium oxychloride refractory brick by fly ash from municipal solid waste incineration

Abstract

The invention discloses a method of making waterproof magnesium oxychloride refractory brick by fly ash from municipal solid waste incineration. The method comprises the following steps: (1) sulfur-containing compound and water are mixed into the fly ash and stirred evenly to make stabilized slurry, the heavy metals are stabilized and CaO is turned to Ca(OH)2 during this process. (2) The aqueous solution of MgO and MgCl2 is added into the stabilized slurry to make magnesium oxychloride slurry by being stirred evenly. (3) The magnesium oxychloride slurry is cured to make magnesium oxychloride gel, (4) and the magnesium oxychloride aggregate is prepared by crushing the magnesium oxychloride gel. (5) The blended slurry is prepared by mixing metastable material, alkali metal hydroxide, Na2SiO3, magnesium oxychloride aggregate and water, (6) after being stirred, molded and cured, the waterproof magnesium oxychloride refractory brick is obtained. The waterproof magnesium oxychloride refractory brick made by this invention combines two materials, the geopolymer gel and the magnesium oxychloride gel, which possess different properties of fire resistance and water resistance. It is confirmed that the coexistence of geopolymer gel and magnesium oxychloride gel achieves the multi-stage solidification and stabilization of heavy metals and improving the water resistance of magnesium oxychloride refractory brick.

Dependencies are inferred from the claim text.