EFFECT OF CALCIUM NITRITE ON HYDRATION REACTION OF BLAST FURNACE SLAG

• Published in: Cement Science and Concrete Technology Vol. 73; no. 1; pp. 44 - 51
• Main Authors: OSAKI, Shuya, ATARASHI, Daiki, SONG, Hyeonjin, SUDOH, Yuhji
• Format: Journal Article
• Language: English; Japanese
• Published: Japan Cement Association 31.03.2020
• Subjects: AFm phase; Blast furnace cement; Blast furnace slag; C-S-H; Calcium nitrite; Environmental loading reduction; Gypsum; Nitrite type-hydrocalumite
• ISSN: 0916-3182; 2187-3313
• DOI: 10.14250/cement.73.44

In order to investigate the effect of calcium nitrite addition on the hydration reaction of blast furnace slag, Ca(OH)2-blast furnace slag paste was prepared and compared with the effect of gypsum addition. At the same time, the effect of calcium nitrite on the hydration of blast furnace cement was also examined. In the case of addition of gypsum, the reaction was stagnant after 14 days, and AFt was confirmed as the main hydration product. By contrast, The hydration reaction of blast furnace slag was continuously promoted by calcium nitrite addition and formed AFm（NO2）. The amount of C-S-H production also increased. The hydration reaction of blast furnace slag and base cement in blast furnace cemente is promoted by calcium nitrite, therefore, it is considered that calcium nitrite can be expected as an activator for blast furnace cement.