//Results from the validation of bio-oil and bio-char

Results from the validation of bio-oil and bio-char

15 March 2020

The profitability of second-generation ethanol production may increase if the solid lignin residue is valorised to an added-value product. One possible route, which was investigated in AGROinLOG, is hydrothermal liquefaction. That is a method based on high temperature and pressure enabling the conversion of a solid material into a major liquid fraction and a minor solid, char, fraction.  In AGROinLOG we characterized these two fractions and evaluated their potential in applications such as a biofuel, as additive in asphalt, as an adhesive or resin, as energy pellet, as soil improvement pellet and as a filling material in concrete based on available information.

The analysis of the bio-oil indicates that the bio-oil produced does not fully reach the threshold values for applications such as a drop in transportation fuel without further upgrading. One possibility would be to use the bio-oil without upgrading as a marine bunker fuel.

The HTL-process was run focusing on maximizing the bio-oil production instead of the biochar production. Therefore, only a small fraction ended up as biochar. This biochar consisted mainly of ash and had a low heating value and was therefore not suitable for heat production, as was initially intended as the use of the biochar. The char was evaluated with respect to its potential as soil improver and it was concluded that the quality is insufficient for that application. Furthermore, the char quality did not reach the standards for the potential application as a filler material in concrete. Therefore, future work on HTL of straw and other lignocellulosic raw material should focus on the main, bio-oil, fraction and its upgrading to added-value products. The achieved results are in line with previous research, i.e. the HTL oils have properties which are different from those of diesel and biodiesel, e.g. different viscosity and heating value which limits its use as transportation fuel without prior upgrading.

2020-05-06T09:09:23+00:00 March 15th, 2020|