Abstract: Solid fuel can be converted into a clean hot flue gas with a low content of volatile organic compounds (VOC's), NOx and dust, and clean ash with a low carbon content by means of a stage-divided thermal reactor, where the conversion process of the solid fuel is in separate vertical stages (from below and up): ash burn-out, char oxidation and gasification, pyrolysis, drying, and a gas combustion stage where gas from the gasifier is combusted.

Abstract: Exhaust gas, produced in a thermal reactor (1) that is fed with solid fuel can be cooled and in a gas cooler (4) which produce a condensate that is further cooled in a condensate cooler (7) which produce energy. By using air moisturizing and particle separation technology the exhaust gas and the excess condensate can be clean and the energy efficiency of the plant can be increased. The method can be used for a broad spectrum of fuels and conversion technologies.

Abstract: Hot gas, produced in a thermal reactor (1), can be cooled in a cylindrical cooling reactor (4) by leading the gas tangentially into the evaporative cooler through and inlet duct (2) whereby the gas perform a rotary movement in the evaporative cooler, and by injection water droplets into the gas at one or more injection zones (3) in such an amount and in such a way that the gas temperature due to water evaporation is reduced to below 400° C. The dry cooled gas can now leave the reactor through the outlet duct (5) and be cleaned for particles in a dry filter (7) and energy can be recovered in a condensing unit (8). Hereby, a compact cooling, cleaning and energy recovery system is obtained, which is cheap and simple and has low maintenance costs, and which moreover has a high efficiency degree and good environmental qualities. The method can be used for a broad spectrum of fuels and conversion technologies.

Abstract: Solid fuel can be converted into a clean hot flue gas with a low content of volatile organic compounds (VOC's), NOx and dust, and clean ash with a low carbon content by means of a stage-divided thermal reactor, where the conversion process of the solid fuel is in separate vertical stages (from below and up): ash burn-out, char oxidation and gasification, pyrolysis, drying, and a gas combustion stage where gas from the gasifier is combusted.

Abstract: Heat can be recovered from hot gas produced in a thermal reactor (1), by injecting water into the gas at one or more injection zones (4) in such an amount and in such a way that the gas temperature due to water evaporation is reduced to below 400° C., preferably below 300° C., possibly below 150-200° C., and the gas dew point becomes at least 60° C., preferably at least 70° C., possibly 80 or 85° C. The gas can then be led through a condensing heat exchanger unit (8), where at least some of the gas contents of water vapour are condensed, and the condensing heat can be utilized for heating of a stream of fluid, mainly water. Hereby, a method for production of hot water is obtained, which is cheap and simple and has low maintenance costs, and which moreover has a high efficiency degree and good environmental qualities The method can be used for a broad spectrum of fuels and conversion technologies.