Manufacture of carbon storage sintered body using microwave-selective and high-speed heating techniques

Abstract

Microwave sintering of fly ash samples with large amounts of unburned carbon and CaCO3 was examined in this study. To this end, CaCO3 was mixed with fly ash sintered body to fix CO2. The decomposition of CaCO3 was observed when the raw material was heated to 1000 ℃ using microwave irradiation; however, a sintered body containing aragonite was obtained when the raw material with water was heated to 1000°C. Further, carbides in the fly ash could be selectively heated by controlling the microwave irradiation. The microwave magnetic field created a temperature gradient of 100°C in a narrow region of 2.7 µm or less in the sintered body, and it helped suppress the CaCO3 decomposition of the mixture in sintering. By storing water in the gas phase, CaCO3, which is difficult to sinter with conventional heating, can be sintered without decomposing.