脱硫石膏强度及耐水性改善方法研究综述

Review on improvement methods of desulfurization gypsum strength and water resistance

针对脱硫石膏强度及耐水性改善方法和改性机理做了系统的归纳与分析。详细阐述了水泥、各种矿物掺合料、有机硅防水剂以及其他有机乳液等对脱硫石膏及其复合胶凝材料的强度和耐水性的影响,对各种改性方法的作用机理、优点以及不足之处进行了讨论。结果表明:掺入适量的水泥和矿物掺合料时会生成水硬性产物,脱硫石膏的强度和耐水性得到一定的改善,但是掺入过量时会造成不利的影响;水泥、粉煤灰和脱硫石膏之间的比例变化会对胶凝体系的强度和耐水性产生较大的影响;有机硅防水剂可以在脱硫石膏表面形成一层疏水性薄膜,显著提升脱硫石膏的耐水性,当与矿物掺合料复合作用于脱硫石膏时可以得到更好的力学性能和耐水性能;其他类型的有机防水剂均能改善脱硫石膏的耐水性,但是大部分会改变脱硫石膏的晶体形貌,对脱硫石膏的强度和耐水性产生不利影响;目前脱硫石膏的改性材料都比较复杂,单独作用时综合性能不佳,需要进一步研究与探讨更加简单、有效的改性材料和方法。

The improvement methods and modification mechanism of desulfurization gypsum strength and water resistance were systematically summarized and analyzed.The effects of cement,various mineral admixtures,silicone waterproofing agents and other organic emulsions on the strength and water resistance of desulfurization gypsum and its composite cementitious materials were described in detail.The mechanism,advantages and disadvantages of various modification methods were discussed.The results show that adding appropriate amount of cement and mineral admixtures will produce hydraulic products,the strength and water resistance of desulfurization gypsum can be improved,but excessive addition will cause adverse effects.The ratio of cement,fly ash and desulfurization gypsum has a great influence on the strength and water resistance of the cementitious system.Silicone waterproofing agent can form a hydrophobic film on the surface of desulfurization gypsum,which can significantly improve the water resistance of desulfurization gypsum.When it is combined with mineral admixtures,better mechanical properties and water resistance can be obtained.Other types of organic waterproofing agents can improve the water resistance of desulfurization gypsum,but most of them will change the crystal morphology of desulfurization gypsum,which will adversely affect the strength and water resistance of desulfurization gypsum.At present,the modified materials of desulfurization gypsum are complex,and the comprehensive performance is not good when acting alone.More simple and effective modified materials and methods need to be further studied and discussed.