SCI和EI收录∣中国化工学会会刊

Chinese Journal of Chemical Engineering ›› 2019, Vol. 27 ›› Issue (5): 1125-1131.DOI: 10.1016/j.cjche.2018.09.023

• Chemical Engineering Thermodynamics • Previous Articles     Next Articles

Investigation of Al2O3 and Fe2O3 transmission and transformation during the decomposition of phosphogypsum

Jie Yang1, Bin Zhu2, Liping Ma1, Hongpan Liu3   

  1. 1 Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China;
    2 School of Environmental Science & Engineering, Huazhong University of Science & Technology, Wuhan 430074, China;
    3 College of Materials and Chemical Engineering, Chongqing University of Arts and Sciences, Chongqing 402160, China
  • Received:2017-12-19 Revised:2018-08-25 Online:2019-06-27 Published:2019-05-28
  • Contact: Liping Ma
  • Supported by:
    Supported by the National Natural Science Foundation of China (21666016).

Investigation of Al2O3 and Fe2O3 transmission and transformation during the decomposition of phosphogypsum

Jie Yang1, Bin Zhu2, Liping Ma1, Hongpan Liu3   

  1. 1 Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China;
    2 School of Environmental Science & Engineering, Huazhong University of Science & Technology, Wuhan 430074, China;
    3 College of Materials and Chemical Engineering, Chongqing University of Arts and Sciences, Chongqing 402160, China
  • 通讯作者: Liping Ma
  • 基金资助:
    Supported by the National Natural Science Foundation of China (21666016).

Abstract: Phosphogypsum (PG) is a solid waste produced in the phosphate fertilizer industry and is environmentally harmful. The decomposition of PG to recycle calcium and sulfur is a proper way to reutilize PG. Current work aims at enriching the basic theory of coal decomposition process of PG. The emphasis was laid on the exploration of impact of main impurities on the process. On the other hand, according to Reaction Module, Equilib Module, and Phase Diagram Module of FactSage, the simulation computation was done on the systems of pure gypsum mixed with coal, with or without impurities for avoiding other impurities interference. Later, possible reactions in the process were deduced. Additionally, experiments were conducted in a TG-DTA integrated thermal gravimetric analyzer and a tube furnace. The products from the experiments were characterized and analyzed to verify the accuracy of theoretical calculations. The results showed that these impurities can change the decomposition process of PG. For example, aluminum oxide was transformed to calcium sulfoaluminate, while iron oxide was transformed to dicalcium ferrite. Furthermore, the results help to further improve the basic theory of phosphogypsum decomposition.

Key words: Phosphogypsum, Reductive decomposition, Simulation calculations, Aluminum oxide, Iron oxide, Ternary diagram

摘要: Phosphogypsum (PG) is a solid waste produced in the phosphate fertilizer industry and is environmentally harmful. The decomposition of PG to recycle calcium and sulfur is a proper way to reutilize PG. Current work aims at enriching the basic theory of coal decomposition process of PG. The emphasis was laid on the exploration of impact of main impurities on the process. On the other hand, according to Reaction Module, Equilib Module, and Phase Diagram Module of FactSage, the simulation computation was done on the systems of pure gypsum mixed with coal, with or without impurities for avoiding other impurities interference. Later, possible reactions in the process were deduced. Additionally, experiments were conducted in a TG-DTA integrated thermal gravimetric analyzer and a tube furnace. The products from the experiments were characterized and analyzed to verify the accuracy of theoretical calculations. The results showed that these impurities can change the decomposition process of PG. For example, aluminum oxide was transformed to calcium sulfoaluminate, while iron oxide was transformed to dicalcium ferrite. Furthermore, the results help to further improve the basic theory of phosphogypsum decomposition.

关键词: Phosphogypsum, Reductive decomposition, Simulation calculations, Aluminum oxide, Iron oxide, Ternary diagram