Diatomaceous earth is a kind of biogenic siliceous sedimentary rock, mainly composed of ancient diatom remains. Its chemical composition is mainly SiO2, containing a small amount of Al2O3, Fe2O3, CaO, MgO, K2O, Na2O, P2O5 and organic matter. The main uses of diatomite are filter aids, fillers, adsorbents, catalytic carriers, environmentally friendly building materials and so on.