Quality\nand Storage Properties of Upgraded Fast Pyrolysis\nBio-Oil for Marine Transport

In-depth data on the long-term storage quality of upgraded\nfast\npyrolysis bio-oil, SDPO (stabilized and deoxygenated FPBO), was produced,\nreflecting its usability as marine fuel. Stability of the SDPO (∼5\nwt % oxygen) was good based on a long-term storage stability study\nand new accelerated aging method. The fuel properties of SDPO and\nits 30% blends with marine fuels remained stable over a storage period\nof one year. Some fuel properties of the analyzed SDPO batch require\nconsideration to meet the specifications for marine distillate fuel,\nnotably, density, viscosity, cetane number, flash point, acid number,\nwater content, carbon residue, and ash content. By removal of light\ncomponents, the flash point of SDPO could be improved. Development\nneeds for the analyses were identified. An accelerated aging test\nfor SDPO was developed in the project. The oxidation stability and\nlubricity methods should be developed and validated for the SDPOs.\nThere are not yet standards or internationally approved methods for\nchlorine and sulfur analyses either for FPBO or for SDPO. On the other\nhand, there is not yet a limit for chlorine in the content of marine\nfuels in ISO 8217:2017. The boiling point range of SDPO is much wider\nthan that of marine fuels. Methodology is needed to ensure that the\nSDPO batch used does not have a tendency to form precipitate in blending\nwith marine fuels, and blending protocols are needed for large batches\nof SDPO. It was also observed that SDPO production is not yet standardized\nand may lead to variations within different batches. Attention is\nneeded also on aspects that were not covered, such as decomposition\nproducts, corrosivity, and additives. Noted is also that SDPO could\nbe more appropriate for marine distillate fuels, since high temperatures\nare needed to lower the viscosity of the residual fuels to the appropriate\nrange for use in marine diesel engines.