Understanding the effect of triethanolamine on grinding and hydration of blast furnace slag, focusing on the degrees of slag consumption and C(-A)-S-H formation
Jihoon Lee, Ahyeon Lim, Hyunuk Kang, Dongho Jeon, Namkon Lee, Chi Sun Poon, Juhyuk Moon
Abstract
This study investigated the effect of the use of triethanolamine (TEA) on grinding blast furnace slag (BFS) for enhancing hydration performance of slag cement . Raw BFS was pulverized with different dosages (0.02, 0.1, and 0.5 wt%) of TEA then various experiments including the quantification of degrees of slag consumption and C(-A)-S-H formation were conducted. As a result, with increasing TEA content, the aluminate reaction was accelerated while the silicate reaction was retarded. At 0.02 wt% TEA, the change in the fineness and hydration products was barely observed. Meanwhile, at 0.1 wt% TEA, a remarkable enhancement in compressive strength was measured (around 40 % increase). The improvement was explained by (1) a refinement of the slag fineness, (2) an increase in the slag reaction, and (3) porosity reduction. However, although 0.5 wt% TEA still promotes the formation of AFm phases, the hydration of the slag was not enhanced as much as that of TEA 0.1 wt% because of significantly delayed silicate reaction.