Preparation and hydration of Belite-Ye'elimite-Ternesite clinker based on industrial solid waste

Abstract

Belite-Ye'elimite-Ternesite (BYT) clinker is a new system of environmentally friendly clinker with low firing temperature and low CO2 emission,which about 30% lower CO2 emissions than ordinary silicate cement. In this paper, the effects of sintering temperature and sintering time on the physical phase composition as well as the evolution of hydration kinetics and the physical phase composition of BYT clinker were investigated using industrial and natural raw materials. The results showed that the optimum sintering temperature should not exceed 1200 °C and the sintering time was 60–120 min when the designed content of C2S was 30%− 70%, ye'elimite was 30%− 50% and ternesite was 0–15%. In addition to the main phases (C2S, ye'elimite and ternesite), intermediate phases such as CA, C3A and C12A7 were also formed in the clinker.The hydration rate of BYT system was quite fast.When the content of ye'elimite was certain, too much belite or ternesite will slow down even hinder the hydration of ye'elimite.The hydrations such as AFt, AFm, AH3, Strätlingite and C4AHx were found in this clinker. The cement has a high early strength and then continues to grow slowly, still reaching 46 MPa after 90d at a high water-cement ratio.

Keywords

• Belite-ye'elimite-ternesite；mineral composition；formation kinetics； hydration