Optimization design of low-density and high-strength ceramic proppants by orthogonal experiment

This study mainly focused on an orthogonal optimization design of low-density and high-strength ceramic proppants prepared by low-grade bauxite and feldspar that met the standard requirements. The orthogonal experimental design of L25 (53) was employed to study the significance sequence of three factors, including milling time of bauxite, milling time of feldspar, and sintering temperature. The results show that the particle size of feldspar is the most important factor for the performance of the proppants. The longer the milling time of feldspar is, the finer the particle size of feldspar is, and the easier it is to form liquid phase at a lower temperature. For the breakage ratio, the optimal experimental combination is bauxite milled for 4 h, feldspar milled for 8 h, and sintering temperature of 1280°C. The proppants prepared by the optimal combination have bulk density of 1.48 g cm−3, apparent density of 2.7 g cm−3, breakage ratio of 4.07% under 52 MPa closed pressure, and acid solubility of 2.15%.