Study Progress on Inorganic Fibers from Industry Solid Wastes and the Key Factors Determining Their Characteristics

Compared to basalt and glass fibers, the production of inorganic fiber from industry solid wastes is an effective method to not only save natural resources but also recycle waste resources. Because the preparation of the fibers requires high temperature treatment, the production process is associated with high energy consumption and high carbon emissions. How to resolve these problems is a current research challenge in this field. Herein, we reviewed the study progress on these fibers and further discussed the key factors determining their characteristics, including chemical composition, melt structure, and viscosity of melt. In production, the matching of solid waste blends containing enough total content of SiO2 and Al2O3, and a suitable amount of MgO and CaO, is beneficial to the structure control of the melt. The study found that the melt consisted of Q2 and Q3; and that Q3 content more than Q2 was more suitable for fiber production and its performance improvement. Such a melt structure can be achieved by controlling the degree of depolymerization and the temperature. New ultrasonic technology can shorten the homogenization time; its application is hoped to save energy and reduce carbon emissions. These conclusions will offer important guidance for the development of inorganic fibers from industry solid wastes in the future.