Optimization of wet-process phosphoric acid for high-quality phosphogypsum.

Autor: Xuyang Fan, Chenyu Zhou, Tingting Xiao, Haoran Wang, Hanjun Wu, Zhongjun Li, Zhiquan Pan, Hong Zhou
Předmět:
Zdroj: Physicochemical Problems of Mineral Processing; 2024, Vol. 60 Issue 5, p1-15, 15p
Abstrakt: The chronic accumulation of phosphogypsum (PG) has resulted in significant environmental contamination issues within the wet-process phosphoric acid (WPPA) industry. An innovative technical route for transforming PG into a resource has been achieved through the introduction of floc flotation and acid cleaning in WPPA. The floc flotation using cationic polyacrylamide as a flocculant and micro lotion, which is composed of dioctyl phthalate, polyoxyethylene(10)nonylphenyl ether, kerosene, and n-octanol as a collector, has been performed. The effect of floc flotation on product quality and the underlying mechanisms were investigated by XRF, FT-IR, SEM, and 2-dimensional fractal dimension analysis. The optimal parameters were determined through a factor experiment, which yielded the following results: floc flotation temperature 65 °C, cationic polyacrylamide 180 g/Mg, collector 1.08 kg/Mg, and flushing sulfuric acid concentration 20%. The resulting PG exhibited a high grade of 95.01%, whiteness of 70.8%, and gypsum recovery of 93.52%. Furthermore, the soluble phosphorus and soluble fluorine levels are below 0.1%. In the flotation process, the combination of polyacrylamide and collector effectively separated fine organic matter and siliceous material with a hydrophobic bubble, facilitating their upward movement and subsequent separation from PG. The new WPPA, which exhibits enhanced product quality and reduced production costs, can be utilized extensively within the WPPA. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index