利用焦宝石和钾长石制备低密高强陶粒支撑剂的研究

Preparation of Low-density and High-strength Ceramic Proppant by Using Flint Clay and K-Feldspar

以焦宝石和钾长石为原料,在1380~1480℃下烧结制备了低密高强陶粒支撑剂,研究了烧结温度对支撑剂性能的影响。结果表明:1420℃烧结制备的20/40陶粒支撑剂性能最佳,其体积密度为1.56 g/cm^3,视密度为2.72g/cm^3,在52 MPa闭合压力下的破碎率为6.32%。在烧结过程中,钾长石软化分解生成的长石玻璃相降低了支撑剂的烧结温度,同时玻璃相的生成有利于Al_2O_3和SiO_2的相互扩散,促进了莫来石相的形成与生长。另外,长石玻璃相填充于坯体的莫来石相之间,使得支撑剂较致密,从而提高了支撑剂的力学性能和化学稳定性。

The low-density high-strength ceramic proppant was sintered from 1380 ℃ to 1480 ℃ using flint clay and K-feldspar as the raw materials,and the effect of sintering temperature on its properties was investigated.The results show that the 20/40-mesh proppants sintered at 1420 ℃ presented the best performance with crush ratio of 6.32%under 52 MPa pressure,the bulk density of 1.56 g/cm and the apparent density of 2.72 g/cm^3.During the sintering process,the feldspar firstly softens,then decomposes,and finally changes into the glass phase which would lower the sintering temperature of proppant.Meanwhile,the presence of glass phase also favors the mutual diffusion of Al_2O_3 and SiO_2,and the formation and growth of mullite grains.The proppants have much higher density as the mullite grains were filled with the feldspar glass,and thus present the better mechanical strength and chemical stability.