Our paper presents a technology for obtaining solid fuel in the form of briquettes intended for firing fluid boilers operating at high capacity heating stations and heat and power stations. Combustion of biomass in a fluid boiler is subject to stringent limitations concerning the chlorine, sodium and potassium contents in the fuel. One should particularly note chlorine corrosion that can only be minimized by reducing the chlorine content in the fuel below 0.06%. A result of this study will be complete utilization of biomass resources available in National Parks in the form of chips, shrubs, grasses, sedges and biomass produced by cultivating energy crops, such as energy willow. This led to the development of a technology for the production of solid fuel in the form of briquettes or fragments thereof, containing no more than 0.06% of chlorine. In turn, the use of nonforest biomass was increased by 30%.