The invention provides a preparation method for compact zirconite overflow
brick with high breaking-resistance and low expansion. The method comprises the following steps: (1) adopting
zircon sand having a ZrSiO4 content more than or equal to 98.5% as a starting
raw material; (2) carrying out acid cleaning for the
zircon sand: a
hydrochloric acid solution is adopted for immersing the
zircon sand, followed by washing through water, and atmospheric
drying; (3) calcinating the acid cleaned zircon sand; (4)
grinding the calcinated zircon sand in a stirring mill according to the following ratio, by weight, 99.0-99.4% of the zircon sand (having a ZrSiO4 content more than or equal to 99.7%), 0.4-0.8% of TiO2, 0.1-0.2% of
phosphoric acid; (5)
drying the
slurry by baking: a screw dehydrator is adopted for
drying; (6) crushing the
powder, and carrying out screening through a vibrating screen having 30 meshes; (7) carrying out isostatic pressing; (8) carrying out
sintering. According to the present invention, due to establishments of a specific forming institution and a specific
sintering institution,
thermal shock resistance of the products is improved; the overflow
brick having characteristics of larger size, no visible blowholes, no melted holes and no
slag corrosion is produced successfully; high-temperature breaking-resistance of the overflow
brick is raised; refiring cubical expansivity of the overflow brick is reduced;
glass corrosion resistance of the overflow brick is improved so as to prolong service life of the overflow brick.