Preparation and Properties of Porous Mullite Base Low-Density High-Strength Proppants

Commonly used resin compound proppant has some shortages such as poor roundness and sphericity,low crush resistance,large quantity of resin needed,high cost and so on.To solve these problems,compound low-density high-strength proppant had been developed based on porous mullite ceramisites.The optimum mass fraction and content of resin had been worked out through evaluation of the unmodified and modified proppant with FT resin.Porosity,pore size distribution and micrograph of proppant had been studied by mercury intrusion porosity and scanning electron microscopy,and the mechanism of enhancement on compound proppant was analyzed.The results showed that when resin mass fraction was 35%,the ceramisites filled effectively with resin had the highest density of 1.18 g/cm3.The open porosity decreased by 62% compared with porous ceramisites and the crush resistance improved significantly because resin and ceramisites form an interlocking network structure.Then the impregnated matrix were coated with resin (resin content 5%),the particles were surrounded completely with resin.Its porosity dropped to 1.06% with the apparent density of 1.90 g/cm3.Crush ratios were 2.17% and 2.81% under 52 and 69 MPa closing pressure,respectively,which meet the technical requirements of the industry standard and company standard.