Turning Waste into Treasure: Preparation of Gypsum Fibers from Flotation Phosphorus Tailings and Their Use as Paper Fillers

Phosphorus tailings are solid waste generated from phosphate ore processing, and their prolonged accumulation consumes significant land area and poses a substantial risk to soil and groundwater quality. This study innovatively converts phosphorus tailings into gypsum fiber for papermaking, thereby addressing the issue of excessive accumulation of phosphorus-rich tailings. Experiments were conducted to investigate the effects of slurry concentration, stirring speed, and reaction temperature on the length of gypsum fibers; and the prepared fibers were used as paper fillers for papermaking to investigate the effects of gypsum fiber lengths, mixing ratio, and retention amount on the performance of paper. The findings indicated that at a slurry concentration of 9%, a stirring speed of 50 rpm, and a reaction temperature of 55℃, the resultant gypsum fibers exhibited increased length, elevated aspect ratio. The 100 μm homogeneous gypsum fiber incorporated into paper exhibits superior mechanical strength compared to shorter or irregular gypsum fibers. The research findings present a novel method for the effective and valuable utilization of phosphorus tailings, resulting in solid waste reduction and pollution abatement, while providing a more environmentally friendly source of functional fillers for the paper industry, thereby generating both ecological benefits and potential economic gains.