METHOD OF PREPARING GYPSUM BINDER Russian patent published in 2001 - IPC

FIELD: cement industry, more particularly manufacture of building products. SUBSTANCE: method of preparing gypsum binder from acid waste of hydrogen fluoride production comprises neutralizing acid waste of hydrogen fluoride production and simultaneously grinding it and followed by granulation with water in which 10-40 wt % of hydrofluoric acid production waste are further added to fluoride production acid waste from slime storages, namely fluorogypsum with moisture content from 0 to 20%. The resulting mixture is neutralized with slime-containing reagent in amount of not more than stoichiometric amount, and mixture cooled to 70-80 C during neutralization process is granulated. EFFECT: optimization of process for preparing binder, higher degree of hydration of fluoranhydrite and greater initial strength of granules without decrease in final strength thereof. 1 tbl