Method for preparing alpha-semi-hydrated gypsum seed crystal from natural gypsum

(22) 26.09.2023

(43) 12.01.2024

(57) The invention provides a method for preparing an alpha-type semi-hydrated gypsum seed crystal by using natural gypsum, which is characterized by comprising the following steps: S1, mixing the natural gypsum, a salt solution and a crystal modifier to obtain blended slurry; s2, adjusting the pH value of the solution of the blended slurry to 7-9, heating and carrying out crystal transformation treatment to obtain alpha-type semihydrated gypsum slurry; and S3, filtering the alpha-type semi-hydrated gypsum slurry while the alpha-type semi-hydrated gypsum slurry is hot, drying and crushing to obtain the alpha-type semi-hydrated gypsum seed crystal. According to the preparation method, fine-grained natural gypsum is taken as a raw material, under the action of the novel crystal modifier, the alpha-type semi-hydrated gypsum seed crystal with a complete and uniform crystal structure is prepared by adopting a normal-pressure salt solution method, and meanwhile, the properties such as breaking strength and compressive strength of the alpha-type semi-hydrated gypsum can be improved.
(71) Wuhan Inst Technology