Research On The Clay-siliceous Crushed Stones-lime Hydro-thermal Synthesis Systems And Application

In the new building material, one kind mainly maintained the silicate concrete product by the calcareous material and the siliceous material through the high temperature steam which formed by hydro-thermal synthesis reactions to obtain the priority promotion and the application. The industry waste slag fly ash or the river sand is used as the siliceous material. But the massive siliceous crushed stones pile up as solid waste disposals in our country excessively because of the clay content.In view of current the clay is generally thought as the harmful ingredient in the sand-lime autoclave product. This article has designed the hydro-thermal synthesis system of clay-siliceous crushed stone- cement-lime in which the clay took as a component. Through study the hardenite of hydro-thermal synthesis the compressive strength, the relative surface area, the hydration water content and the PH value are researched. The influence of different hydro-thermal synthesis method on hardenite has analyzed. The different clay content which has effect on the performance of hardenite has study especially .The research indicated that, the clay can react under the condition of hydro-thermal synthesis , within the range of certain clay mixing amount, the clay neither will reduce the performance of hardenite, still help to harden the improvement of hardenite performance instead.Through XRD and the SEM microscopic test method, the microstructure of hydro-thermal synthesis hardenite has studied .The result indicated that, the mainly hydration products is CSH (B), Tobermorite and a small amount of granular Hydrogarnet. No component of clay was found after hydro-thermal reaction of mixture, which explained the clay participated in hydro-thermal reaction reactions completely. The different condition of hydro-thermal produce hydration products CSH (B) and Tobermorite with different degree of crystallinity. The different clay content also produce the different degree of crystallinity hydrated product, under the suitable condition of hydro-thermal, the crystalline state of hydrated product are better with 10%~15% clay content. The hydrated product is dense.According to the conclusion of the study on the hydro-thermal synthesis hardenite, moreover clayish crushed stone content silicon dioxide above 85%, which is possible to pruduce aeroconcrete used as siliceous material. This experiment reports using clayish crushed stone for production of aerated concrete. B05 and B06 grade aerated concrete were prepared successfully using different clay content. Hydro-thermal synthesis reaction, mix ratio, gas-forming and performance of aerated concrete are analyzed. The proper mix ratio and important processing parameters were identified. The microstructure of aerated concrete with clayish crush stone was analyzed by means of XRD and SEM. The results indicate that the hydration products of clayish aerated concrete were CSH (B), Tobermorite and a small amount ofgranular Hydrogarnet. A homogeneous and densified microstructure of aerated concrete was obtained. B05 and B06 grade aerated concrete were prepared in the lab used solid waste disposals, which achieved the standard request. If it can be applied in the industrial production, it will not only benefit from the utilization of solid waste disposals and environmental protection, it also prominent economic benefits and social benefit, it is of far-reaching significance and great.