| 摘要 |
PURPOSE:To obtain the title gypsum which scarcely causes disintegration or powdering during handling, easily gives uniform soil and does not require any step of drying and firing after granulation, by adding waste liquor of alcoholic fermentation and optionally water to a mixture of gypsum semihydrate and humus and granulating the mixture. CONSTITUTION:After 2-10pts.wt. (on a dry basis) humus is added to 100pts.wt. gypsum semihydrate such as alpha-semihydrate concomitantly formed in a wet- process phosphoric acid manufacturing plant, which is optionally neutralized with slaked lime, or while 2-10pts.wt. (on a dry basis) humus is mixed with 100pts.wt. gypsum semihydrate, 5-25pts.wt. waste liquor having a viscosity of 20-500cp obtd. from alcoholic fermentation and optionally water are added thereto. The mixture is hydrated and granulated by using a granulator of, e.g., dish type, drum type, paddle type, etc. to obtain gypsum having a moisture content of 5-10wt%. |
