Effective reduction of sintering temperature and breakage ratio for a low‐cost ceramic proppant by feldspar addition

Abstract

The second grade bauxite and feldspar were used to synthesize ceramic proppant materials. Phase structure and microstructure of the samples were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. It was found that the feldspar, as a sintering aid, was beneficial to generate liquid phase during the sintering process. The formed liquid phase, not only promoted the densification of the samples, but also reduced the sintering temperature. With the content of feldspar increasing, the sintering temperature gradually decreased. When the content of feldspar was 4 wt.%, the breakage ratio of the samples was reduced to the lowest level of 2.2% at 1400°C under 52 MPa closed pressure, which met the requirement of Chinese Petroleum and Gas Industry Standard (SY/ T 5108-2014). Moreover, the sintering temperature was reduced by 100°C compared with the proppants without adding feldspar.

Effects of CaCO3 additive on properties and microstructure of corundum‐ And mullite‐based ceramic proppants

“…If calcium carbonate was further added (Figure D), the abundant glass phases appeared, and the gaps in the skeleton structure formed by interweaving of rod‐shaped mullite and polygon corundum were filled with the glass phase, and the crystal grain boundaries became obscure due to grains melt. It would not be conducive to the improvement of crush resistance . Figure C,E,F showed the SEM images of the samples with 5 wt.% additive at different sintering temperatures (1260°C, 1350°C, 1450°C).…”

“…High crush resistance demonstrates high content of alumina due to the positive correlation between alumina content and strength . It would lead to higher manufacture costs and incompatibility to large‐scale production . Therefore, it is of practical significance to reduce production costs.…”

The Effect of Sintering Temperature on Phase Evolution and Sintering Mechanism of Ceramic Proppants with CaCO3 Addition

“…However, ceramic proppants have a higher density and are more costly than quartz sands due to high proportion of bauxite in raw materials. Ma et al 2 prepared ceramic proppants using 92 wt% bauxite and the samples sintered at 1400°C possessed the lowest breakage ratio of 2.2% under 52 MPa closed pressure. Zhao et al 3 fabricated ceramic proppants with 93 wt% calcined bauxite, which exhibited better performance with a breakage ratio of 3.22% under 52 MPa closed pressure sintered at 1355 °C.…”

Preparation and optimization of a low cost, high breakage resistance ceramic proppant special for the coal‐bed methane

“…High cost of the raw materials will lead to high consumption of high-grade bauxite. The high sintering temperature will result in high consumption of heat energy [11]. The high density of ceramic proppants will cause difficulties of carrying by the fracturing fluid and increasing the whole cost of the hydraulic fracturing process [5,12].…”