a process for the production of Self Glazed Ceramic Insulator Using Waste Rice Husk Ash and Waste.

Abstract

The invention discloses a formula of a ceramic for an insulator ceramic body and a preparation method of the insulator ceramic body. Ceramic insulators are very important product in world because of zero water absorption, excellent physical, mechanical and chemical properties. Huge amount of materials like rice husk ash, waste glass and other industrial waste are present as waste materials in Bangladesh which are used to produce cost-effective self glaze ceramic insulator. The concept of utilization of solid wastes embraces the basic principles of recovery, recycling and converting to value added products. Recovery and recycling is a well-recognized process. However, it again generates waste which results in a disposal problem. Beneficial effects of a technical scheme of the invention comprise that the formula contains specific proportions of rice husk ash and waste glass (soda lime silica glass) and rice husk ash and waste glass are sintered into Mullite and Wollastonite to improve a mechanical strength and self glazed ceramic body and a hot and cold performance of a ceramic material. The self glazed insulator ceramic body obtains physical properties, insulating properties and mechanical properties. To improve the physical and mechanical properties, the surface of the normal ceramic insulator must be covered with a thin layer of glaze to get zero water absorption and to increase its mechanical strength (modulus of rupture). The glazing process typically requires a number of additional operations and can consume a great deal of time, raw materials and energy. There are some particular ceramic compositions which can develop their own glaze layer by a self-glazing phenomenon, when they are fired under the appropriate conditions. Self glazed ceramic insulators are one of such value added products where rice husk ash and waste glass / soda-lime glass can be used as raw materials. Normal commercial insulators are mainly made in clay, quartz, k-feldspar and Na-feldspar. Self glazed ceramic insulator was made by mixtures containing certain amount of rice husk ash, clay, quartz, soda-lime silica glass powder and k-feldspar. Soda-lime silica glass is used as alternative of Na-feldspar. The samples were fired at different temperatures in the range 1075 – 1150 0 C with soaking time of 1hour and the physico-mechanical properties and microstructure were investigated. The optimum temperature and optimum properties are determined to compare with standard properties of ceramic insulator. The results revealed that the soda lime silica glass powder acts as fluxing agent instead of Na-feldspar when it is used as an additive in ceramic mixture and rice husk ash as silica source. The prepared self glazed ceramic insulator using rice husk ash and soda-lime silica glass powder increases the firing shrinkage and modulus of rupture with increasing temperature and after a certain temperature, these values decrease. The glossiness values increase with increasing firing temperature. The phase formation of the self glazed ceramic insulator indicates mullite, quartz and wollastonite.