Method for preparing hemihydrate gypsum powder
from phosphogypsum by means of atmospheric salt solution process, and hemihydrate gypsum powder
(22) 01.12.2023
(43) 05.06.2025
(57) The present invention relates to the technical field of waste recovery, and provides a method for preparing a hemihydrate gypsum powder from phosphogypsum by means of an atmospheric salt solution process, and a hemihydrate gypsum powder. The method comprises: preparing a slimy from a mixed liquid of a salt and a crystal modifier and purified phosphogypsum, wherein the crystal modifier is a betaine compound with pH responsiveness; and adjusting the pH value of the slurry on the basis of the isoelectric point of the crystal modifier and the required length-diameter ratio of hemihydrate gypsum crystals, subjecting the slurry to a constant-temperature dynamic reaction, and filtering same, thereby obtaining a hemihydrate gypsum powder, wherein when the pH value of the slurry is greater than the isoelectric point of the crystal modifier, the length-diameter ratio of the hemihydrate gypsum crystals increases, and when the pH value of the slurry is less than the isoelectric point of the crystal modifier, the length-diameter ratio.
(71) Guangdong Brunp Recycling Technology Co., Ltd.) [CN/CN]
(84) ARIPO (BW, CV, GH, GM, KE, LR, LS, MW, MZ, NA, RW, SC, SD, SL, ST, SZ, TZ, UG, ZM, ZW), RAE (AM, AZ, BY, KG, KZ, RU, TJ, TM), A‘A (AL, AT, BE, BG, CII, CY, CZ, DE, DK, EE, ES, FI, FR, GB, GR, IIR, HU, IE, IS, IT, LT, LU, LV, MC, ME, MK, MT, NL, NO, PL, PT, RO, RS, SE, SI, SK, SM, TR), OAPI (BF, BJ, CF, CG, CT, CM, GA, GN, GQ, GW, KM, ML, MR, NE, SN, TD, TG)
