Technological possibilities of pyrolysis of high-molecular organic substances for liquid engine fuel production

An attempt to evaluate the technological capabilities of wood and wood waste pyrolysis for obtaining liquid motor biofuel in comparison with oil refining was made. It was shown that the compared technologies have much in common: substances with a high carbon content (> 70 %) are processed; processing is carried out using high temperatures; the processed products are gaseous, liquid and solid substances, etc. However, pyrolysis has undeniable advantages over oil refining: pyrolysis is a single-stage process, less sensitive to the quality of the processed raw materials, since it was specially developed for processing non-marketable products and waste; less sensitive to the moisture content in the raw materials; the products of wood and wood waste pyrolysis practically do not contain sulfur, which is important from an environmental point of view; and, most importantly, pyrolysis wins over oil refining in energy efficiency, since oil refining uses only 30–40 % of the energy allocated for this, while the energy efficiency of pyrolysis is 60–70 %. Energy consumption of pyrolysis is directly proportional to the moisture content of the processed raw material (wood and wood waste), however, the energy consumption can be compensated for by a feature inherent only to wood pyrolysis, that is the exothermic stage of cellulose and lignin decomposition. A qualitative and quantitative assessment of the products obtained was carried out. In this regard, the pyrolysis technology is inferior to oil refining, i.e. liquid pyrolysis products make up only 23–26 % (65–75 % in oil refining). It was shown that the liquid products obtained as a result of raw material pyrolysis are suitable as liquid fuel.