Thermochemical Conversion of Biomass into 2nd Generation Biofuel

Abstract

Bioenergy is considered the largest contributor to the renewable and sustainable energy sector worldwide, playing a significant role in various energy sectors such as heating, electricity supply, and even in replacing fossil fuels in the transportation sector. As part of renewable, low-carbon energy systems, bioenergy can also ensure atmospheric carbon sequestration, provide numerous environmental and socio-economic benefits, and thus contribute to achieving global climate change goals, as well as broader environmental, social, economic, and sustainable development objectives. The use of bioenergy can significantly reduce our carbon footprint and thus contribute to improving the environment. While bioenergy conversion of biomass produces some amount of carbon dioxide, similar to traditional fossil fuels, its impact can be minimized by replacing forest biomass with fast- growing trees and energy crops. Therefore, fast-growing trees and energy crops are the primary raw materials for bioenergy. The results of the research in this publication confirm the high efficiency of biomass depolymerization through thermochemical conversion. The principle of continuous biomass conversion was used at a process temperature of 520 ◦C. The experiments were carried out in the Biomass Gasification Laboratory at the AgroBioTech Research Center of the Slovak University of Agriculture in Nitra. The biomass used for the experiments was from energy-producing fast-growing willows, specifically the varieties Sven, Inger, and Express. The aim was to determine the amount of biochar produced from each of these tree species and subsequently to investigate its potential use for energy purposes. During the experiments, 0.106 kg of biochar was produced from 1 kg of Inger willow biomass, 0.252 kg from 1 kg of Express willow biomass, and 0.256 kg from 1 kg of Sven willow biomass. A subsequent goal was to determine the production of gas, which can also be used for energy purposes. The biofuel samples obtained were subsequently subjected to thermogravimetric analysis to determine moisture content, volatile matter, and ash content. The ash content in dry matter ranged from 6% to 7.28%, while the volatile matter in dry matter was between 92.72% and 94%. The moisture content in the samples ranged from 1.7% to 2.43%. These results may contribute to innovative insights into biomass depolymerization and help define optimized parameters for thermochemical conversion, as well as the required biomass composition, with the goal of generating second-generation biofuels in the most cost-effective way.