Analysis on the preparation and microstructure characteristics of cinder based ceramics

As an industrial by-product of coal combustion for energy production, cinder, recognized as an environmental pollutant, accounts for about 70% after coal was burned. Utilization of it as resource has been tried in many fields. However, utilization level of cinder is still low, and to find a novel way to utilize cinder efficiently is urgent. Cinder includes much calcium and silicon, similar to those of clay, which means that it can be one of the raw materials for ceramic sintering. In this research, the ceramic tiles with excellent performance were obtained, with up to 60% cinder added. By orthogonal experiments and range analysis, clay is the most important factor, following by feldspar and quartz. The effects of sintering temperature on the bend strength and pores in cinder ceramics have been discussed. The samples with more clay and less feldspar have greater bend strength at high sintering temperature of 1190°C. Cinder ceramics were systematically characterized by the X-ray diffraction (XRD), scanning electron microscope (SEM) and Energy Dispersive Spectrum (EDS). There are lots of phases exist in these samples. The possible crystal phases that exist in cinder ceramics were identified, which are anorthite, quartz and hematite. And the quartz phases exist signally, anorthite are relatively well-distributed, hematite distributed sporadically.