水泥对脱硫石膏性能影响的试验研究

为改善脱硫石膏的性能,使其在建筑工程中应用更为广泛。通过对不同水泥掺量的石膏进行抗压强度和抗折强度试验,探究石膏强度与水泥掺量的关系;并通过扫描电镜实验(SEM)和X射线衍射实验(XRD)对单掺水泥石膏强度变化的微观机制进行分析。研究结果表明:水泥掺入脱硫石膏后可以一定程度上改善脱硫石膏的力学性能,提高脱硫石膏的强度。通过微观机理分析发现,水泥-石膏混合体系中会产生钙矾石,由于钙矾石的膨胀以及硅酸钙水化后生成的水化硅酸钙凝胶填充于石膏孔隙,使石膏趋于密实,从微观上解释了石膏强度的增长机制。但由于钙矾石的膨胀具有双重作用,因此存在水泥的最经济掺加量,实验研究确定脱硫石膏中水泥的最经济掺加量为10%。

Experimental study on the influence of cement on the performance of FGD gypsum

In order to improve the property of FGD gypsum and make it widely used in construction engineering. Based on the different cement content of gypsum on compressive strength and flexural strength test, this paper explores the relationship between the strength of gypsum and cement content. And scanning electron microscopy (SEM) and X-ray diffraction (XRD) are used to analyse the micro mechanism of single doped gypsum cement strength change. The research results show that the mechanical properties of FGD gypsum can be improved to a certain extent after the cement mixed with FGD gypsum, and the strength of the desulfurization gypsum can be improved. With the help of the microscopic mechanism analysis, finding that the cement gypsum mixed system can produce ettringite, and due to ettringite expansion and calcium silicate hydration after the formation of hydrated calcium silicate gel filled to the pores of the gypsum, gypsum become compact, which explaines the strength of gypsum growth from the mechanism microscopic. However, due to the dual role of ettringite expansion, cement has the most economical dosage. Experimental study on determining desulfurization gypsum in cement the economic content is 10%.