Silicon carbide waste as a source of mixture materials for cement mortar

• Published in: Frontiers of environmental science & engineering 2017-10, Vol.11 (5), p.47-54, Article 2
• Main Authors: Jiang, Zhengwu, Ren, Qiang, Li, Haoxin, Chen, Qing
• Format: Article
• Language: English
• Subjects: Calcium hydroxide; Calorimetry; Cement; Cement mortar; Cemented carbides; Differential scanning calorimetry; Earth and Environmental Science; Environment; Fluidity; Mixtures; Mortars (material); Research Article; Scanning electron microscopy; Shrinkage; Silicon; Silicon carbide; Silicon carbide waste; Slaked lime; Special Issue—Recycling Materials from WEEE; Strength; Thermogravimetry
• ISSN: 2095-2201; 2095-221X
• DOI: 10.1007/s11783-017-0974-y

This paper presents an investigation of the feasibility of recycling silicon carbide waste （SCW） as a source of mixture materials in the production of cement mortar. Mortars with SCW were prepared by replacing different amounts of cement with SCW, and the properties of the resulting mortars, such as the fluidity, strength and shrinkage, were studied in this work. Thermogravimetry-differential scanning calorimet;＇y and scanning electron microscopy were employed to understand the reasons for the property changes of the mortars. The results indicate that SCW decreases the initial and l-h fluidity of fresh mortar but improves the loss of fluidity. The mortar with SCW exhibits a lower strength at 3 d and7 d but a higher strength at 28 d and 56 d compared to the control. The shrinkage rate of cement mortar with SCW shows an obvious decrease as the replacement ratio increases. In addition, the content of calcium hydroxide in hardened paste also shows that SCW has some impact on the hydration of the cement-SCW system. The microstructures of the hardened paste also show evidence for a later strength change of mortar containing SCW. This work provides a strategic reference for possibly applying SCW as a mixture material in the production of cement mortar.