Study On Preparation And Application Of Non-Clinker Red Mud Cement

Red mud is the production process of alumina from industrial waste, there is no basic use; The cement industry is faced with the pressure of resources and the environment; Therefore the use of red mud to the preparation of a no clinker cement is a beneficial attempt.Through crushing, drying and grinding process were highly active material of red mud powder. Use the test methods such as X-ray diffraction, scanning electron microscopy(SEM) to analyze the characteristics of red mud powder, the test shows that the main ingredient in red mud powder for calcite and perovskite, also contain a certain amount of silicon aluminium elements; And red mud particles small, irregular shape, between red mud particles together.To red mud powder active contrast test with mineral powder, fly ash, it is concluded that red mud powder has the very good volcanic activity; The hydration products of cement powder has good excitation effect of red mud, active excitation agent provides reference for red mud. Hydrated lime, desulfurization gypsum, sodium sulphate, sodium hydroxide, sodium silicate as exciting agent, by one yuan, binary and multicomponent compound excitation, selected based on the intensity of red mud base without the basic formula of cement clinker, the red mud powder: hydrated lime: desulfurization gypsum = 8:2:1. On this basis, the research on the basic formula of modified fly ash and mineral powder, it is concluded that red mud base without modification formula of cement clinker, the red mud powder: hydrated lime, kuangfen, desulfurization gypsum = 8:2:2:1.With the aid of their hydration products by means of microscopic analysis, explore the cementing mechanism of red mud base without clinker cement. For red mud powder- lime system, cementation can be divided into physical and chemical cementation of cement; Physical cementation can be divided into the crystallization and ion effect, filling effect; Chemical cementation can be divided into ash, carbonation, the main products including ash reaction is hydrated calcium silicate, etc. For basic matching main difference is that the difference of hydration products due to the presence of gypsum will be generated ettringite. Is ettringite there and make the strength increase, and excess of desulfurization gypsum make specimen cracking is also because of the existence of ettringite. For red mud base without the limit of the clinker system damage was caused by a lack of red mud particle hardness, kuangfen in the modified formula can to a certain extent, reduce the defect, the existence of mineral powder can produce chemical cementation and filling effect.Passed the test of the red mud fineness, water cement ratio experiment, calcining process performance of modified ratio were studied. According to the characteristics of the red mud base without cement clinker, the admixture in cement, mining filling, practical application aspects, such as red mud brick for further exploration.