METHOD FOR PRODUCING A CONDITIONED FUEL

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The aim of the method according to the invention is producing conditioned fuels from biomass and combustible materials, in that drying takes place by minimizing the toxic material load, and the formation of corrosive alkali halogenides during combustion is simultaneously suppressed. In a first step, a base is added to the wet biomass in order to release the ammonia as ammoniac. The biomass is then heated and subjected to a vacuum. The ammoniac is thereby removed from the biomass, while the sulfur compounds remain in the biomass. In a second process step, the biomass is dried. Due to the increased pH value, the corrosion potential of the biomass relative to the steel used in the dryer is decreased at the same time. The presence of alkali earth ions when using an alkali earth base causes forming of compounds with the alkali earth ions during the drying process, said ions have a significantly lower volatility under combustion conditions than alkali chlorides. The chloride concentration in the flue gas is thereby significantly reduced, and corrosion of the heat exchanger is significantly limited. The sulfur compounds still present in the fuel are converted to sulfur oxides forming a protective sulfate layer on the heat exchangers with the oxides present in the flue gas.