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Hydrothermal carbonization is modern low-temperature method to improve characteristics of peat and other types of biomass as a fuel. The influence of methods at different temperatures and different reaction time the physical-chemical and energy properties of the resulting biochar is studied. Characteristics of the initial peat and hydrochar were determined such as elemental composition, ash content, moisture content, heating values. It has been established that with an increase in temperature and reaction time, yield of hydrochar oxygen in it decreases (from 33.1% - initial peat to 19.47% - hydrochar obtained at 230 °C), but carbon (from 52.09% - initial peat to 68.17% - hydrochar obtained at 230 °C) and heating value increases. Also was observed leaching the inorganic component from hydrochar into the water.

This document explains the advantages and disadvantages of three types of bed materials used in two-stage pyrolytic processing of wood waste into the synthesis gas. The process combines pyrolysis and subsequent high-temperature heterogeneous cracking of volatiles in the carbon residue fixed bed (obtained by raw material pyrolysis), the inert material (aluminum oxide ceramics) or dolomite. Experimental data characterising the dependence of the gas yield, its chemical composition, the calculated lower heating value and tar content on the process parameters are presented. The optimisation of parameters and the bed material mostly depends on the process purpose: a large-volume inert material bed is preferable for using in burners in the cracking zone, it allows to obtain the most calorific gas with a lower calorific value up to 13 MJ / m³; whereas a carbon residue at a temperature of above 1,010 °C is a preferable bed material in gas engines (when the tar content is less than 50 mg/m³); and a carbon residue at a temperature less than 1,000 °C is the best for the synthesis of liquid fuels (H2 to CO ratio reaching its maximum). Using dolomite turned up to be impractical because of its thermal instability and high amount of both CO2 and H2O in the gas product. [ABSTRACT FROM AUTHOR]