METHOD OF MANUFACTURE OF GYPSUM-CONCRETE BLOCKS AND RAW MIX FOR THEIR MANUFACTURE Russian patent published in 1997 - IPC

FIELD: manufacture of wall gypsum-concrete stones on gypsum- cement-sand binding material. SUBSTANCE: the offered method includes supply to continuously operating mixer, first, of part of metered sand and saw-dust, and then, remaining sand and water with setting inhibitor. Loaded components are mixed for, at least, 20 s, then, gypsum-cement-sand binder is added and all components are mixed for, at least, 40 s, then, mix is placed into vibratory forms and pressed for 17-25 s with pressing force of 3.5- 4.7 MPa, frequency of 3000 vibrations per minute and amplitude of 1-2 mm. Forms are removed and blocks are held still for, at least, 20 min. Mix includes, %: gypsum plaster, 30.92-34.0; pozzuolanic portland cement, 5.46- 6.0; sand, 53.22-58.34; sawdust, 4.404.95; boiled down filtrate of wastes of production of citric acid, 0.33-0.38. EFFECT: higher efficiency. 2 cl, 2 tbl