Environment·Health·Safety

Effect of autoclave parameters and impurities on preparation of α-hemihydrate gypsum from phosphogypsum

  • Jinwen CHEN ,
  • Yun YI ,
  • Hui ZHANG ,
  • Fei LIU ,
  • Lin YANG ,
  • Jianxin CAO
Expand
  • 1. School of Chemistry and Chemical Engineering,Guizhou University,Guiyang 550025,China
    2. Engineering Research Center for High Efficiency Utilization of Industrial Waste of Guizhou Province
    3. Key Laboratory of Guizhou Province for Green Chemical Industry and Clean Energy Technology
    4. Guizhou Institute of Products Quality Inspection & Testing

Received date: 2021-05-25

  Online published: 2022-03-18

Abstract

By analyzing the phase composition,relative crystallinity,drying compressive strength and microscopic morphology of the samples after autoclaving of phosphogypsum,the effect of autoclavic temperature,holding time,liquid-solid ratio and impurities on the preparation of α hemihydrate phosphogypsum by autoclavic compaction was studied.The results showed that the drying compressive strength of the samples obtained after autoclaving of phosphogypsum was positively correlated with the relative crystallinity of α hemihydrate gypsum crystals.When the autoclaved temperature was 130 ℃,the holding time was 3~5 h,and the liquid-solid ratio was 0.25,the obtainedα-hemihydrate gypsum had high relative crystallinity,high drying com-pressive strength,complete crystal micromorphology and small aspect ratio.Impurities in phosphogypsum would affect the me-chanical strength of autoclaved samples.After the phosphogypsum was washed with water,the α hemihydrate gypsum with a 2 h flexural strength of 7.3 MPa and a drying compressive strength of 32.8 MPa could be prepared under the conditions of au-toclaved temperature of 130 ℃,holding time of 3 h and liquid-solid ratio of 0.25,which was in line with the requirement of α30 strength grade in JC/T 2038—2010“α-type high strength gypsum”.

Cite this article

Jinwen CHEN , Yun YI , Hui ZHANG , Fei LIU , Lin YANG , Jianxin CAO . Effect of autoclave parameters and impurities on preparation of α-hemihydrate gypsum from phosphogypsum[J]. Inorganic Chemicals Industry, 2022 , 54(3) : 91 -96 . DOI: 10.19964/j.issn.1006-4990.2021-0303

References

[1] 王荣谋, 马丽萍, 郑大龙, 等. 磷石膏流化分解过程颗粒的黏附特性[J]. 硅酸盐通报, 2017, 36(3):791-796.
[2] 赵红涛, 李会泉, 包炜军, 等. 磷石膏中微量含氟物相的光谱分析[J]. 光谱学与光谱分析, 2015, 35(8):2333-2338.
[3] 李展, 陈江, 张覃, 等. 磷石膏中磷、氟杂质的脱除研究[J]. 矿物学报, 2020, 40(5):639-646.
[4] 代典, 余学军, 潘志权. 浮选-化学法联用处理磷石膏制备高纯石膏[J]. 非金属矿, 2020, 43(1):44-48.
[5] 孙志立. 中国磷石膏资源化利用的展望与思考[J]. 硫酸工业, 2016(1):55-58.
[6] 童俊. “十三五”磷石膏处理处置现状及展望[J]. 建材发展导向, 2018, 16(16):6-11.
[7] 陈家伟. 磷石膏综合利用处置方案[J]. 广州化工, 2019, 47(1):109-111,120.
[8] 李逸晨. 石膏行业的发展现状及趋势[J]. 硫酸工业, 2019(11):1-7,13.
[9] LU W, MA B, SU Y, et al. Preparation of α-hemihydrate gypsum from phosphogypsum in recycling CaCl2 solution[J]. Construction and Building Materials, 2019, 214:399-412.
[10] DUAN Z, LI J, LI T, et al. Influence of crystal modifier on the pre-paration of α-hemihydrate gypsum from phosphogypsum[J]. Con-struction & Building Materials, 2017, 133:323-329.
[11] 杨林, 张冰, 周杰, 等. 磷石膏制备α型高强石膏及其转化过程研究[J]. 建筑材料学报, 2014, 17(1):147-152.
[12] 何玉龙, 陈德玉, 刘路珍, 等. 磷石膏制备高强石膏工艺研究[J]. 非金属矿, 2015, 38(2):1-4.
[13] 罗东燕, 邱树恒, 陈霏, 等. 用蒸压法将磷石膏制备α半水石膏的研究[J]. 新型建筑材料, 2015, 42(9):23-26,46.
[14] SINGH M. Effect of phosphatic and fluoride impurities of phospho-gypsum on the properties of selenite plaster[J]. Cement and Conc-rete Research, 2003, 33(9):1363-1369.
[15] 曾鲁平, 乔敏, 王伟, 等. 无碱速凝剂对硅酸盐水泥早期水化的影响[J]. 建筑材料学报, 2021, 24(1):31-38,44.
Outlines

/