Study On Pyro-synthesis Of Several Typical Cementitious Minerals With Conventional And Microwave Heating

As a kind of the cementitious minerals, the cement, in which some minerals are much interested in by some researchers, has been becoming more and more important in the national economy.The cement clinker mainly includes four minerals:tricalcium silicate, dicalcium silicate, tricalcium aluminate and brownmillerite. This thesis is focus on the effect of two different heating methods on synthesizing these four minerals as well as contrasting between the two methods. For more details, its emphasis is on the effect of conventional external heating method and microwave internal method heating as well as different soaking time and different cooling methods on composition and microstructure of above four minerals. And difference analysis is also included in this thesis. In its studies, XRD (X-ray diffraction) and SEM (scanning electron microscopy) are used. After a large number of experiments, the data and images obtained are processed、analysized and discussed. Besides, a few analyses and investigates are on formation mechanism and process of topical minerals are taken according to relevant physical chemistry theory. From these studies, some research results have been gotten which are as follows.· Comparing with synthesizing the cementitious minerals in the conventional heating, the microwave heating can decline the temperature points of mineral forming, because its characteristic of the rapid heating can speed up the formation of the minerals, and make more tightness, so the microstructure of cementitious minerals in the microwave heating can be more uniform and density. Through the analysis and study, we believe that there are some advantages in synthesizing the cementitious minerals in the microwave heating.· Comparing with the conventional heating, the microwave heating can also lead to some negative factors::The maximum count value of synthesizing minerals will be lower than that in the electric heating, but the one of by-products is higher in the mineral forming process. In addition, microwave synthesizing can’t guarantee the preservation in the high temperature, especially in the heating and synthesizing certain minerals. But to realize high temperature soaking is easily in electric way.· Study on the different ways of cooling, we also made some experiments, mainly on synthesizing C2S in electric way. Through the analysis and study, we found experimental results different from some previous research report.