Pyrolysis of Waste Biomass: Technical and Process Achievements, and Future Development—A Review

Pyrolysis has been applied in the human economy for many years, and it has become a significant alternative to the production of chemical compounds, including biofuels. The article focuses mostly on recent achievements in the technical and processing aspects of pyrolysis. The aim of the review is to present the latest research on the process of waste biomass pyrolysis to fuel production. The paper describes the mechanisms of the pyrolysis process, composition, and properties of the obtained fractions, namely pyrolysis gas, bio-oil, and biochar. Additionally, the technical aspects of the pyrolysis process are mentioned, with particular attention to the construction of the reactors. The process of waste biomass pyrolysis allows for obtaining many chemical compounds (second-generation biofuels). Optimization of the pyrolysis process allows obtaining the desired products that are applied in the chemical industry, energy, and transport. The application of pyrolysis gas, oil, and biochar as valuable chemical compounds are related to the intensifying effects of climate change, biofuel production, and waste management in accordance with the principles of sustainable development. In recent years, there has been large-scale research into the use of renewable energy sources through pyrolysis. This will make it possible to significantly reduce the carbon footprint and produce second-generation biofuels in a sustainable manner. Current research into the mechanisms of pyrolysis processes is promising, and will therefore provide access to clean and low-cost compounds that will have broad applications in the energy, chemical, agricultural, and transportation industries.