The task of investigation was development of main approaches for biomass preparing and processing for use it in industrial furnaces and boilers instead of natural gas. The direct combustion of sawdust and sunflower husks and gasification of different kinds of biomass were studied. The burnout time of sawdust and sunflower husks particles was defined and demands for fuel preparing for use it in rotary kilns were elaborated. Special burners and heat regimes for sunflower husks combustion in rotary kilns were developed and implemented. Original technology of biomass air gasification was proposed and studied. It was shown, that producer gas has low calorific value sufficient for use it in boilers and engines. Industrial gas generator of 1,8 MW capacity and dual fuel burners for joint or separate combustion of producer and natural gas were developed and implemented at steam boiler. Technical solutions piloted in industrial scale could be efficiently applied in manufacturing sectors and energy sector.

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One-stage melting-converter method for the vitrification of high-level radioactive wastes (HLRAW) was developed and investigated. This method includes the concentration (evaporation), calcination, and vitrification of the HLRAW in one-stage process inside a melting converter. Converter consists of a water-cooled conical metal melting chamber. Capacity for the saturated salty solution is 200 l/h and the capacity for the glass-HLRAW mixture is about 100 kg/h. Calculations showed that at a melt temperature of 1150°C, a cooling-water temperature of 20°C and a thickness of the melt lining of 15 mm the heat flux through the walls is about 75 kW/m2 and wall temperature is about 55°C. Thermal analysis showed that at the burner heat transfer rate of 460 kW the heat transfer rate for heating and melting of the charge is 20 kW, the heat transfer rate for evaporation of water from the solution is 100 kW, and the heat losses are 240 kW. Therefore, a thermal efficiency of the converter is about 26%. To keep a melt lining on the vault of converter and around a burner nozzle the special design two-phase closed thermosyphons are used. Design and heat transfer characteristics of these thermosyphons are discussed. Calculations have been made for heat removal of the melted glass and fissionable nuclides poured into the metal containers during first 500 hours.