It is important to recover the maximum bio-oil energy in the dry bio-oil. Figure 4.9
shows the percentage of the raw bio-oil energy that is recovered in the oil fraction and the
percentage that is lost in the water fraction, for the three different C-ESP temperatures. At
the selected optimum C-ESP temperature of 70 °C, the energy recovered in the oil
fraction is 98% of the total bio-oil energy. In case of fractional condensation of bio-oil
vapors produced from birch bark pyrolysis, described in Chapter 3, the energy recovered
in the oil fraction was 90% of the total bio-oil energy. Therefore, in terms of energy
recovered in the oil fraction, lignin proves to be a better biomass feedstock when
compared to the birch bark