Method of collecting anhydrous sodium sulfate from fly ash
AssigneeIndustrial Technology Research Institute
InventorsChien-Wen LIN, Yi-Liang TSAI, Chao-Wu LIAW, Woan-Shiow TSERNG, Chih-Lung CHIN, Shih-Hsien LIU
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Abstract
A method of collecting anhydrous sodium sulfate from fly ash includes heating a purified sodium sulfate solution to 60° C. to 80° C., and adding a precipitation promoter to the purified sodium sulfate solution to precipitate anhydrous sodium sulfate crystal. The method further includes cooling the purified sodium sulfate solution and the anhydrous sodium sulfate crystal to 35° C. to 55° C. for precipitating more anhydrous sodium sulfate crystal, and collecting and drying the anhydrous sodium sulfate crystal.
Claims8
A method of collecting anhydrous sodium sulfate from fly ash, comprising:
- (i) evenly mixing water and fly ash, and removing liquid and keeping a solid;
- (ii) dissolving the solid with water at 40° C. to 70° C. to obtain a first solution, and adjusting pH value of the first solution to 9 to 11;
- (iii) adding a heavy metal capture agent to the first solution to form a precipitate, and removing the precipitate to obtain a second solution;
- (iv) heating the second solution to 60° C. to 80° C., and adding a precipitation promoter to the second solution to precipitate anhydrous sodium sulfate crystal;
- (v) cooling the second solution and the anhydrous sodium sulfate crystal to 35° C. to 55° C. for precipitating more anhydrous sodium sulfate crystal;
- and
- (vi) collecting and drying the anhydrous sodium sulfate crystal.
Dependencies are inferred from the claim text.