Gogotsi O. Improvement of the operating and design parameters of high-temperature furnaces with electrothermal fluidized bed for heat treatment of carbon materials

The dissertation is aimed at solving of an important scientific and technical problem of enhancing the efficiency and reliability of furnaces for heat treatment of carbon materials with electrothermal fluidized bed (EFB) by improving theiroperating and design parameters of their operation. The problems were solved by experimental and theoretical studies of hydrodynamics and heat-and-mass transfer in furnaces with EFB. Experimental studies of hydrodynamics were performed on a “cold” model of a furnace with an EFB, which allowed to determine the modes that ensure uniform processing of material. A method for calculating furnaces with EFBwas proposed. On its basis, a pilot furnace of 10 kg / h capacity was developed and fabricated. Its tests were carried out, as a result, the possibility of heating natural graphite was proved and the basic requirements tostructural elements of a furnace were determined. A two-stage cooling of the final product was proposed, which includes a straight-tube cooler of a fixed bed with parallel channels and a cross-flow cooler with a checkerboard arrangement of water-cooled pipes. On the basis of mathematical simulation, it was proved that intensification of the cooling process of the final product in straight-tube coolers of the first stage is possible by reducing the diameter of the channels and application of sections that provide mixing of the material. The erosive impact of carbon materials on tube heat-exchange surfaces of a final product coolerdepending on material velocity and pressure was experimentally determined. On the basis of mathematical simulation of cooling of dust containing gases the technology process flow diagram of cooling and cleaning of exhaust gases of a furnace with EFBwas developed.