A numerical analysis of the thermoelectric state of the Acheson furnace was performed and the use of new thermal insulation of blanks that are graphitized was proposed. The expediency of using a single-component heat-insulating charge as thermal insulation is shown. In this case, in comparison with the use of a traditional multicomponent synthetic mixture, not only a decrease in the temperature of the blanks is observed, but also a significant equalization of temperature along the axis of the blanks. Based on the results of measuring the thermophysical properties and numerical simulation of temperature fields in the volume of the Acheson graphitizing furnace, a resource-saving and environmentally efficient carbon heat-insulating mixture was selected, which consists of raw and graphite coke grains 50/50 % (wt.) up to 2 mm in size. Theoretical and experimental studies of the ecological state of kilns and graphitizing furnaces have been carried out. Based on the analysis of the obtained experimental data, the temperature and time dependences of the concentration of carbon monoxide in kilns and graphitizing furnaces are established. The main sources of carbon monoxide formation are determined: under-oxidized carbon materials, aromatic and resinous substances of binder preforms. A set of measures has been developed that can reduce the concentration of carbon monoxide emissions from furnace equipment in industrial conditions. Experimental studies were carried out to determine the temperature dependence of the concentration of carbon monoxide during heating of a multicomponent and one-component heat-insulating charge, which made it possible to establish a reduction in CO emissions by more than 20 % in the case of using the proposed one-component charge. Bibl. 17, Fig. 9, Tab. 3.

The analysis of operational thermal conditions of the furnaces for aluminum scrap remelting is given. It was established that it is necessary to choose refractory materials with aluminum oxide content more than 85 % and the thickness of the thermal insulation should ensure the temperature of the external surfaces not higher than 50 °C when designing the furnaces for lining. On the basis of relevant methods packages of application programs have been developed for design calculations of lining and thermal insulation considering thermal conductivity change of individual layers as a result of their complete or partial impregnation with molten aluminum; calculations of energy balances; the selection of external heating devices with electric or flame heating. The power of the external heat source, the amount of heat spent on heating the scrap to the melting temperature, melting and overheating the melt to the working temperature and heat loss have been taken into account in the energy balance. The heat balance equation is used for determination of the melting time for electrically heated furnaces or the power of burner devices at the desired melting time. In the design calculations, the necessary thicknesses of lining and heat-insulating materials are chosen for all elements of enclosure. With appropriate calculations in dialog mode, it is also possible to change materials and their thickness quickly in case of exceeding the allowable operating temperatures of these materials. Options of using electric tape or wire heaters made of nichrome or EI-626 steel were considered during external heating devices calculations. Flame heating can be implemented using gas burners or liquid fuel nozzles. Further variant calculations based on the developed methods and software made it possible to create a furnace design with a capacity of 600 kW with reduced energy and operating costs for the melting process. Bibl. 14, Fig. 1, Tab. 1.

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