Multiphase analysis of hydrochars obtained by anaerobic digestion of municipal solid waste organic fraction

Digestate is a nutrient-rich substance produced by anaerobic digestion that contains organic, inorganic, and biological matter. The European Nitrates Directive (91/676/EEC) provides regulations regarding the wider implementation of digestate. Owing to significant amount organic matter in digestate, it can be utilised as solid biofuel, soil amendment substance, or substrate for activated carbon production. However, by-products municipal waste wet fraction cannot used such applications because still considered waste. Hydrothermal carbonisation (HTC) was investigated pre-treatment method digestate obtained fraction. HTC carried out at temperatures 180, 200 230 °C residence times 30, 60 120 min. value pressure determined based on water temperature partial gaseous by-products. process resulted changes physical chemical properties hydrochars compared those raw materials. A time min during were optimal energy consumption; this hydrochar exhibited best combustion parameters (specific surface area).