Key words: swine manure, chicken manure, biofuel, sub- and supercritical water, liquefaction, carbonization, gasification, oxidation
Treatment of swine and poultry manure (waste of hazard class III) with water at parameters above its critical point (T > 374 °C, P > 22.1 MPa) is considered as one of the promising methods for their environmentally friendly processing. The works devoted to liquefaction, carbonization, and gasification of swine and chicken manure in sub- and supercritical water are analyzed. The problems associated with the practical implementation of waste processing in supercritical water-oxygen fluid are discussed. Their source is, first of all, the high cost of compressed oxygen, the heterogeneous composition of the wastes and the presence of solid particles an them, precipitation of salts and corrosion of structural materials. It is shown that due to the high water content in the wastes and the low calorific value of the organic matter contained in them, the practical implementation of the process in autothermal conditions will require the use of additional fuel.
doi:10.34984/SCFTP.2022.17.2.003